Support getOccurrences for modifier keywords.
A few touch-ups to the code.
Merge branch 'master' into getOccsForModifiers
Added 'Constructor' to 'isDeclaration' predicate.
Look through constructor parameters if acc. modifier.
Account for variable statements, as they are not declarations.
Added a few tests.
Merge branch 'master' into getOccsForModifiers
Catch modifiers in sourcefiles.
Added more tests.
Fixed comment.
Merge branch 'master' into getOccsForModifiers
Parse computed property names
Add grammar errors for computed property names
Add parser tests for computed properties
Emit for computed properties
Emit tests for computed properties
Syntax error for computed properties on method overloads
Update error codes
Checker refactor for FunctionLike and VariableOrProperty