lex: New lexical analyzer module for use in OVN.

I'm determined not to let the terrible style of pseudo-parsing we have in
OVS leak into OVN.  Here's the first step.

Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Andy Zhou <azhou@nicira.com>
Acked-by: Russell Bryant <rbryant@redhat.com>

Makefile.am

@@ -378,4 +378,3 @@ include vtep/automake.mk
 include datapath-windows/automake.mk
 include datapath-windows/include/automake.mk
 include ovn/automake.mk
-include ovn/controller/automake.mk

ovn/TODO

@@ -19,11 +19,6 @@
    Probably should be defined so that the data structure is also
    useful for references to fields in action parsing.
 
-** Lexical analysis.
-
-   Probably should be defined so that the lexer can be reused for
-   parsing actions.
-
 ** Parsing into syntax tree.
 
 ** Semantic checking against variable definitions.

ovn/automake.mk

@@ -127,3 +127,6 @@ ovn_ovn_nbctl_LDADD = ovn/libovn.la ovsdb/libovsdb.la lib/libopenvswitch.la
 bin_PROGRAMS += ovn/ovn-nbd
 ovn_ovn_nbd_SOURCES = ovn/ovn-nbd.c
 ovn_ovn_nbd_LDADD = ovn/libovn.la ovsdb/libovsdb.la lib/libopenvswitch.la
+
+include ovn/controller/automake.mk
+include ovn/lib/automake.mk

ovn/lib/automake.mk

@@ -0,0 +1,2 @@
+lib_LTLIBRARIES += ovn/lib/libovn.la
+ovn_lib_libovn_la_SOURCES = ovn/lib/lex.c ovn/lib/lex.h