Build system should strip unnecessary files from distributables

[raamdev]

@jaswsinc writes (in Slack):

the ⁠⁠⁠⁠src/vendor/bin⁠⁠⁠⁠ directory (and contents) does not need to be in there. Things like ⁠⁠⁠⁠README.md⁠⁠⁠⁠, ⁠⁠⁠⁠CHANGELOG.md⁠⁠⁠⁠, ⁠⁠⁠⁠CHANGELOG.mdown⁠⁠⁠⁠, ⁠⁠⁠⁠README.mdown⁠⁠⁠⁠, ⁠⁠⁠⁠.php_cs⁠⁠⁠⁠, ⁠⁠⁠⁠circle.yml⁠⁠⁠⁠, ⁠⁠⁠⁠.travis-scripts⁠⁠⁠⁠, ⁠⁠⁠⁠.gitkeep⁠⁠⁠⁠, ⁠⁠⁠⁠phpunit.xml⁠⁠⁠⁠, ⁠⁠⁠⁠phpunit.xml.dist⁠⁠⁠⁠, and ⁠⁠⁠⁠Makefile⁠⁠⁠⁠ in some of the dependency directories do not need to be in the final distro either.

In the Lite build, many of the additional dependencies are in there, even though we added support for ⁠⁠⁠⁠require-lite:{}⁠⁠⁠⁠ in ⁠⁠⁠⁠composer.json⁠⁠⁠⁠ via the Phing build system. So this part is not working in the Phing build system.

Related: #146
Related: #141

[raamdev]

We should be excluding from the final distributables anything in the src/ directory that is not necessary for the plugin to run, e.g., src/vendor/monolog/monolog/doc/ and (maybe?) src/vendor/symfony/debug/.

[raamdev]

Noting also that we do have the project_other_zip_tgz_fileset_exclusions property in the .build.props file that could be used to ensure certain files/directories are excluded from the distributable, so maybe we just need to keep the exclusions there more up-to-date?

[jaswrks]

I think if it's something fairly common and easy for us to exclude across all builds for any project, then we should try to do that. An example would be a directory with the name /tests/, which we exclude already. I think a directory named /debug/ or /doc/ could lead us to false-positives in other projects, so those would be good candidates for project_other_zip_tgz_fileset_exclusions.

[jaswrks]

@raamdev See d8ab74b where I've added some additional patterns that are now excluded from all builds, across all projects.