Backport from #2068683: hook_requirements() causes a refresh even when update frequency is set to 'check manually'

Issue #1883154 backport form D6: Translation version should not be more recent than core or module version.

Issue #1071068 by SkyWombat, fortis, Sutharsan: modify l10n_update_project_list() to not do update_projects altering for us, since it does just harm, no good; add our own altering possibility instead

Issue #1057150 by Dematron, jonhattan, Sutharsan: refactor and fix Drush support, now compatible with Drush 4+

Issue #1041852 by s.Daniel: Update module name in .info file to be consistent with project name on drupal.org and elsewhere (backported)

#1009852 by bartl, vividgates, grub3: fix ordering and formulation of JOINs in query so it is PostgreSQL compatible

#1013480 by Zoltan Balogh: fix duplicate entry integrity constraint violation due to non-existent variables

#937298 by grootte, Sutharsan, -redShadow-, myself: check if the database prefix is string for simpletest compatibility