-Started on filtering.
-Started on expanding the grammar to support filtering.
-Replaced priorities by a more generic (scope) construct.
-Removed associativity, since it will be solved in a more generic way as well.
-Implemented scoped alternatives.
-Implemented restricted sorts.
-Added the filtering test to the 'runall' thingy.
-Added TLSort's (sorts that reference out of a scope to the top level sort).
-Fixed an issue with restricted sorts in combination with scopes.
-Partially fixed an issue with self cyclic, nullable, lists nesting in scopes.
-Fixed some issues related to lists in combination with scopes and restricted sorts.
-Made the restricted sorts more restricting.
-Removed some dead code.
-Fixed an some issues with lists in combination with restricted sorts.
-Refuse to handle invalid restricted sort types.
-Allow TLSorts to be used like 'plain' sorts (eventhough it's not really necessary).
-Some cleanup.
-Corrected some field and parameter names.
-Cleaned up the test implementations a bit.
-Made the parser unextendable.
-Renamed the parser implementation.
-Fixed some field access issues.
-Added input based filtering options (precede, match, follow restrictions and requirements).