adding a command-line utility for executing common testing functions
missing delete function on config.
new katest management command "clean_db"
preventing central-server regret

Conflicts:
	kalite/management/commands/katest.py
refactor confirm logic in katest clean_db

Conflicts:
	kalite/management/commands/katest.py
creating securesync subapps.  biggest hacks: having to define empty Meta class on *any* subclass of SyncedModel, doing weird Device stuff in engine.models to avoid circular imports
adding back crypto_login, ROOT_UUID_NAMESPACE in settings is hard-coded and not overridable, small (test) bugfixes to get tests running.
adding missing import
Merge pull request #502 from bcipolli/securesync_subapps

IDOC: Securesync sub-modules
Merge branch 'release-0.10' of github.com:learningequality/ka-lite into release-idoc

Conflicts:
	kalite/securesync/api_views.py
two small (but major) bugfixes
Merge branch 'securesync_subapps' of github.com:bcipolli/ka-lite into release-idoc
Merge branch 'release-0.10' into release-idoc
Merge branch 'release-0.10' of github.com:learningequality/ka-lite into release-idoc

Conflicts:
	kalite/management/commands/katest.py
	kalite/securesync/models.py
	kalite/securesync/views.py
Merge branch 'release-0.10' of github.com:learningequality/ka-lite into release-idoc
Remove auto-killing of all other started servers, since we have PID files.
Quick fix to prevent errors on duplicate exercise and video logs in generaterealdata.
Fixing broken link on register device page.
Merge pull request #538 from jamalex/stop_killing_everything

Remove auto-killing of all other started servers, since we have PID files.
Merge pull request #540 from dylanjbarth/release-0.10

Fixing broken link on register device page.