added 'use' keyword.
added 'use' test case.
added 'trait' keyword.
added 'trait' test case.
added 'interface' keyword.
added 'interface' test case.
added 'implements' keyword.
added test case for classes with an implementation declaration.
added test case: class A extends B implements IC.
Merge pull request #96 from diasbruno/master

Add some php keywords. Fixes #92
Increase PHP version
Add documentation on building. Fixes #85

Thanks @dennisreimann
added back the reviewed haskell syntax.
added haskell test script.
added haskell test to the test runner.
added haskell to the builder.py.
Merge branch 'feature/haskell-syntax' into develop
added C Preprocessors test case.
added haskell demo.
Merge branch 'feature/haskell-syntax' into develop