Basic full form rendering

Dyanmically reading properties from the database
Delete redundant code lines
Rename LayerDataProperty things to Filter
More renaming
More renaming
More renaming
Create a factory to return LayerPropertiesReaders for other JDBC drivers

At this stage no other drivers are implemented
Persist enabled filters to the configuration XML file
Reads configuration from the saved file and merges with db read properties
Add test coverage for Filter, FilterConfiguration, FilterMerge and NodeWrapper
Add test for FilterParser
Some refactoring and add check that filters file exists

You cannot read a document that does not exist
Add tests for FilterConfigurationReader
Add tests for FilterConfigurationWriter