#70 compatibility to Sqlite database

[Christof Efkemann]

The current version of Google Map Integration does not work if Gallery 2 uses a Sqlite database.
This is easily fixed with the attached patch:
- add db schemas for Sqlite
- use getFunctionSql where SUBSTRING was hard-coded before

[Christof Efkemann]

Sqlite compatibility patch

[Karl Newman]

Thanks for the patch. I'll try to get that incorporated shortly.