add tests for not expressions
tests for interchangeability of - and _
Merge pull request #24 from wonja/interchangeable_hyphens_underscores

tests for interchangeability of - and _
tests for escaped quotes
Merge pull request #25 from wonja/escaped_quotes

tests for escaped quotes
Tests for adjacent identifiers that start with hyphens
Merge pull request #26 from wonja/identifiers_with_hyphens

Tests for adjacent identifiers that start with hyphens
Use minitest
comments
added some options
factor constants
better errors
fix path join error
tests for variable_exists function
tests for global_variable_exists function
tests for function_exists function
tests for mixin_exists function
tests for quoted variables and functions
Merge pull request #29 from wonja/introspection_functions

Introspection functions
test for short-circuiting conditional expressions