Added support for building the mecab plugin library (JEN-427)

[tplavcic]

BUG:
libpluginmecab.so is missing from 5.7.10-1rc1
https://bugs.launchpad.net/percona-server/+bug/1534617
JEN-427

DOCS:
https://dev.mysql.com/doc/refman/5.7/en/fulltext-search-mecab.html

INFO:
The library is statically built into libpluginmecab.so on centos and dynamically linked on ubuntu (probably because the packages exists in ubuntu/debian repositories) - although MySQL documentation says it's statically linked on all linuxes - seems it's not.
Where system packages exist it can be built with "-DWITH_MECAB=system" and that will do a dynamic link and will not bundle config and other stuff - we do this on ubuntu/debian.
If you do a "-DWITH_MECAB=<path_to_lib>" it will statically link the library into libpluginmecab.so and bundle config - we do this on centos with some included dictionary (but we currently don't have packages on centos so we build from sources every time - link below).
The change in this PR is basically just adding the option to build with -DWITH_MECAB=system|path to build-binary.sh, debian package (built with system). Rpm has optional build from before, now only the jenkins was changed to use it.

The sources for static builds are from here:
http://jenkins.percona.com/downloads/mecab/

TEST BUILDS:
http://jenkins.percona.com/job/percona-server-5.7-redhat-binary/63/
http://jenkins.percona.com/job/percona-server-5.7-debian-binary/32/
http://jenkins.percona.com/job/percona-server-5.7-debian-binary-notokudb/40/
http://jenkins.percona.com/job/percona-server-5.7-binaries-release/28/

TEST:
DEBIAN CONTENT:

plavi@zoidberg  ~/Downloads  dpkg -c percona-server-server-5.7_5.7.10-1rc1-1.trusty_amd64.deb|grep mecab
-rw-r--r-- root/root     85940 2016-01-14 18:52 ./usr/lib/mysql/plugin/debug/libpluginmecab.so
-rw-r--r-- root/root     15128 2016-01-14 19:06 ./usr/lib/mysql/plugin/libpluginmecab.so

TARBALL CONTENT:

plavi@zoidberg  ~/Downloads  tar -tzvf Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100.tar.gz|grep mecab
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/mysql-test/include/have_mecab.inc
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/mysql-test/suite/innodb_fts/include/mecab.inc
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/mysql-test/suite/innodb_fts/r/mecab_utf8.result
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/mysql-test/suite/innodb_fts/r/mecab_sjis.result
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/mysql-test/suite/innodb_fts/r/mecab_ujis.result
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/mysql-test/suite/innodb_fts/t/mecab_utf8.test
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/mysql-test/suite/innodb_fts/t/mecab_utf8-master.opt
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/mysql-test/suite/innodb_fts/t/mecab_sjis.test
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/mysql-test/suite/innodb_fts/t/mecab_sjis-master.opt
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/mysql-test/suite/innodb_fts/t/mecab_ujis.test
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/mysql-test/suite/innodb_fts/t/mecab_ujis-master.opt
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/dic/
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/dic/ipadic/
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/dic/ipadic/sys.dic
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/dic/ipadic/right-id.def
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/dic/ipadic/matrix.bin
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/dic/ipadic/dicrc
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/dic/ipadic/left-id.def
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/dic/ipadic/char.bin
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/dic/ipadic/unk.dic
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/dic/ipadic/pos-id.def
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/dic/ipadic/rewrite.def
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/etc/
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mecab/etc/mecabrc
Percona-Server-5.7.10-1rc1-Linux.x86_64.ssl100/lib/mysql/plugin/libpluginmecab.so

RPM CONTENT:

[root@t-centos7-64 /]# rpm -ql Percona-Server-server-57|grep mecab
/usr/lib64/mysql/mecab
/usr/lib64/mysql/mecab/dic
/usr/lib64/mysql/mecab/dic/ipadic
/usr/lib64/mysql/mecab/dic/ipadic/char.bin
/usr/lib64/mysql/mecab/dic/ipadic/dicrc
/usr/lib64/mysql/mecab/dic/ipadic/left-id.def
/usr/lib64/mysql/mecab/dic/ipadic/matrix.bin
/usr/lib64/mysql/mecab/dic/ipadic/pos-id.def
/usr/lib64/mysql/mecab/dic/ipadic/rewrite.def
/usr/lib64/mysql/mecab/dic/ipadic/right-id.def
/usr/lib64/mysql/mecab/dic/ipadic/sys.dic
/usr/lib64/mysql/mecab/dic/ipadic/unk.dic
/usr/lib64/mysql/mecab/etc
/usr/lib64/mysql/mecab/etc/mecabrc
/usr/lib64/mysql/plugin/debug/libpluginmecab.so
/usr/lib64/mysql/plugin/libpluginmecab.so

RPM INSTALL:
I have setup the following option:
dicdir = /usr/lib64/mysql/mecab/dic/ipadic
in config file: /usr/etc/mecabrc
(otherwise you get an error on installation)

[root@t-centos7-64 etc]# mysql -uroot -p
Enter password: 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 5
Server version: 5.7.10-1rc1 Percona Server (GPL), Release 1rc1, Revision ba64673

Copyright (c) 2009-2015 Percona LLC and/or its affiliates
Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> INSTALL PLUGIN mecab SONAME 'libpluginmecab.so';
Query OK, 0 rows affected (0.07 sec)

[tplavcic]

I am self approving this since the git change is fairly simple, the magic happens in jenkins and that part is already changed.

[laurynas-biveinis]

@tplavcic, " although MySQL documentation says it's statically linked on all linuxes - seems it's not." - is this something that should be reported upstream as a bug?

[tplavcic]

Seems like that they didn't want to go into detail in documentation so they just put all linuxes into one box since they have non-linux builds also. Possibly they use static linking in most linuxes (they have suse, fedora also...). But on ubuntu/debian there are some system packages with shared library so they link their plugin dynamically with that library. I don't think it's a bug in program but maybe documentation could be a little bit more clearer.

[laurynas-biveinis]

Yep, it's a documentation bug I had in mind