ticket:10 tests added
ticket:10 added class Change and create/update/delete receivers
ticket:10 added migration
ticket:10 signals receivers moved to signals.py and merged in 1 handler
ticket:10 added import signals in __init__.py in hello
Merge branch 't9_models_list' into t10_signals
Merge branch 't8_template_tag' into t10_signals
Merge branch 't10_signals'