#64 group DB-tables by module

[Klaus Darilion]

Hi!

The number of openser's table is constantly growing, thus I would like to have default table names grouped by the module name, e.g.
xcap_xml -> presence_xcap_xml
presentity -> presence_presentity
lcr -> lcr_routes
gw -> lcr_gw
gw_grp -> lcr_gw_grp

I know changing old table names is difficult for compatibility reasons, but newly needed tables could follow this syntax.