Added more data-gateway pattern classes + more rewrites for better usability in web...

Added more data-gateway pattern classes + more rewrites for better usability in web-based applications:
- Added methods values() and entrySet() to Criteria instances
- Added method add() to Result instances
- Added method matchesAnd() which does a boolean check on all criteria on each Storeable instance
- Added DatabaseResult class with no implemented methods (will follow)
- Method doSelectByCriteria() in Base64 database backend is now "basicly finished"
- Added more thrown exceptions to not exit application servers on any thrown exception
Signed-off-by:Roland Häder <roland@mxchange.org>