Adding the parser, configuration files, and PHPUnit tests
Merge the $ignored_functions and $ignored_function_args properties
Standardize basedir to not have a trailing slash
Add better class recognition

`$this`, `self`, and `parent` are now properly filled out within
classes. Adds associated unit tests.
Write errors to STDERR instead of logging them with error_log
Improve CLI usage, add support for JSON config file
Clean up _exit_function()
Update the ignores cache on the fly
Update README.md
General cleanup
Unit tests: combine the two conditionals