Remove GeoTools 2.2 Filter and Expression interfaces

Delete GeoTools 2.2 Filter interfaces
Delete GeoTools 2.2 Expression Interfaces: only way to be sure we won't have a class cast exception.
Cleanup deprecated Expression interfaces and unused classes
Remove GeoTools Expression getType() and getValue( feature ) methods
Remove remaining methods that assume GeoTools Expression - this required the addition of Filters.getExpressionType(expression) utility method.
Filter implementations no longer need factory for ant,or,not.
Remove GeoTools FilterFactory and FilterFactoryFinder.
Remove FilterVisitor and FilterVisitor2: It is time to move on
Remove Filter.filterType
Safe cast to geotools expression, will return null if not possible.
Initial Filter cleanup of and, or and not methods.