added new libraries for logging and convenience
improved function argument rules to get a nicer interface for listener
and visitors
very basic logging configuration
improved test setup: test files are read from the
src/test/resources/function_parse_test -> no ugly String handling within
test class
fixed problem in lexer grammar -> even though new line is supposed to be
skipped, there was another lexer rule defined for matching new line
which resulted to parse problems
improved grammar to make generated interfaces more convenient
added new test sets
made rows and costs values more suitable
removed temp file
parse util changes
defined rules for variable declarations + test