Add Module.const_defined? && _get && _set methods

Add .travis.yml.

Add Literal Tests

Add literal tests for currently working String literals and make notice about literals which yet need to be proper implementation

Use default case in switch statement.

SEGV by adding a new assert

Raise SEGV by using String literal

Add Test Cases (Literals, Enumerable, Exceptions, misc)

remove extraneous cmake build targets