Removed format filter and refactored filters to receive hashmap of arguments
All core filters/functions/tests are now individual classes as opposed to inner static classes
Renamed a few classes, removed some unused code, and just general cleanup of ExpressionParser
More clean up of how filters and arguments are parsed
Renamed SyntaxException to ParserException
Refactored how the test operators are parsed and made the filter operator to be handled like most other operators
Refactoring of how arguments are parsed and compiled in different ways
Officially not supported arguments when getting an attribute of a variable
Major refactoring of filters/tests/functions/macros to prepare for named arguments
Functioning named arguments with unit tests
More named argument tests
More unit tests for named arguments
Removed @ignore annotation from old unit test
Fixes #15
Fix for issue #16
Small code clean up of PebbleEngine
Added some javadoc comments