Add whitelist_patterns option to PhpMnd task

[mgeoffray]

Q	A
Branch	master for features and deprecations
Bug fix?	no
New feature?	yes
BC breaks?	no
Deprecations?	no
Documented?	yes
Fixed tickets	no

As for #160 this PR add a new whitelist_patternsoption to PhpMnd task. It will be used to filter files to be validated.

Example for a Symfony, validate PHP files only in src/ directory

phpmnd:
    whitelist_patterns: ["^src/(.*)"]
    triggered_by: [php]

[mattheo-geoffray]

Hi @veewee @Landerstraeten ,
do you know when the next release is planned?
Thank you!

[Landerstraeten]

Thanks!

[mattheo-geoffray]

@Landerstraeten Thank you!

[j3rrey]

Came here after a year, new account anyways I just wanted to say thank you guys!