refs #218 - Tests and docs for rapidsms.contrib.default
refs #218 - Use self.apps to set router apps in tests
Reset settings by calling set_router or set_backends
Should make it easier to reset the router or backends in the middle of a test.
refs #218 - Removed override_settings for 1.3 compatibility
refs #218 - Nitpicks
Use rapidsms.tests.harness.setting
Use override_settings if it is available
refs #218 - Clarified information about routers + app loading
refs #219 - Updated docs for rapidsms.contrib.echo
refs #219 - Added tests for rapidsms.contrib.echo
Removed redundant method
Noticed by @dpoirier - testRouterMixin._pre_rapidsms_setup() calls set_router() and invokes the superclass method, which now also calls set_router().
refs #219 - Clarification that PingHandler requires precise text
add 0.12 release notes stub
Merge branch 'master' of github.com:rapidsms/rapidsms into docs/contrib/default
refs #218 - Fixes based on comments from @copelco
Merge branch 'master' of github.com:rapidsms/rapidsms into docs/contrib/echo
refs #219 - Updated release notes
Merge pull request #249 from caktus/docs/contrib/echo

refs #219 - Tests and docs for rapidsms.contrib.echo
Merge branch 'master' of github.com:rapidsms/rapidsms into docs/contrib/default

Conflicts:
	docs/index.rst
	docs/releases/0.12.0.rst
set version to 0.12.0dev