Merge pull request #93 from WordPress-Coding-Standards/develop

Add Travis CI integration and a pre-commit hook
Introduce a Function Restrictions Sniff, to handle restriction of different functions groups, each with its own error/warning message.
Merge branch 'develop', remote-tracking branch 'origin' into function-restriction-sniff
Improve FunctionRestrictionsSniff, convert to abstract class
Move existing groups to VIP\RestrictedFunctionsSniff ( switch_to_blog #82 and eval family #81 )
Add warnings about remote calls #85
Flag use of extract() #90
Convert remote calls sniffs to warning instead of errors, as per #85
Change abstract declaration of FunctionRestrictionsSniff, which broke PHPCS
Flag use of custom roles #88
Annotate statements in RestrictedFunctionsUnitTest
Add methods to unit test which yield false negatives
Note false negatives as OK
Add namespaced functions which also yield false negatives
Fix sniff for function definitions, class methods, and namespaced function calls
Make create_function a warning, but keep eval as error
Merge pull request #106 from WordPress-Coding-Standards/function-restriction-sniff

Function restrictions sniff