Fix SQL function comments in console (drag&drop)

See #643
Don't comment out SQL command
Fix javadoc and function count String
Make SQL functions appear only once in the least

Before, the same function was appearing one time for every signature it
had. See #643
Try to fix signatures (not done)
Fix signature condition
Fix signature generation and sort with TreeMap
Write Signature(s) rather than Example usage
Ignore return type (for now)
Refactor and fix PostGIS signatures
Add PostGIS type name
Some small improvements

Still have an NPE with PostGIS _st_dumppoints.
And ST_Dump is not working correctly.
Generate signatures only for nonempty ones
Fix NPE on _st_dumpoints and others
Sort signatures by length
Small cleanup
Add author name
More cleanup
Put null as default Catalog and Schema
Fix signature in test