add backup_migrate, context, ctools, entity, jquery_update, libraries, module_filter, pathauto as submodules

move submodules to the following branch
backup_migrate 7.x-2.4
context 7.x-3.0-beta6
ctools 7.x-1.2
entity 7.x-1.0
jquery_update 7.x-2.3
libraries 7.x-2.0
module_filter 7.x-1.7