Php_parser task

[veewee]

Q	A
Branch	master
Bug fix?	no
New feature?	yes
BC breaks?	no
Deprecations?	no
Tests pass?	yes
Documented?	yes
Fixed tickets	#138

This PR contains a new php_parser task which can be used to do some static code analys on your PHP files. It comes shipped with some default visitors that can be used.

New Task Checklist:

• Is the README.md file updated?
• Are the dependencies added to the composer.json suggestions?
• Is the doc/tasks.md file updated?
• Are the task parameters documented?
• Is the task registered in the tasks.yml file?
• Does the task contains phpspec tests?
• Is the configuration having logical allowed types?
• Does the task run in the correct context?
• Is the run() method readable?
• Is the run() method using the configuration correctly?
• Are all CI services returning green?

Parser NodeVisitor checklist:

• declare_strict_types
• forbidden_class_method_calls
• forbidden_function_calls
• forbidden_static_method_calls
• nameresolver
• never_use_else
• no_exit_statements

Note to myself: Keep an eye on sstalle/php7cc#79. I currently removed the php7cc dependency since I want to keep on track with the phpparser library.

[veewee]

The build failure is not related to the code, but apperently the Windows cmd.exe can't handle more then 8191 characters. We'll need to find a workaround for that one since the CI is failing now. The current size of the command is 9764 characters long.

More info:
http://superuser.com/questions/1070272/why-does-windows-have-a-limit-on-environment-variables-at-all
https://support.microsoft.com/nl-nl/kb/830473
http://stackoverflow.com/questions/3205027/maximum-length-of-command-line-string