refactored view error handling
extracted assert_node_for_path method
extracted assert_authentication method
extracted assert_permissions method
extracted assert_active_user method
extracted assert_post_parameter method
refactored microblogging error handling
PEP-8-ified microbloggin/views.py
Merge remote-tracking branch 'origin/master'

Conflicts:
	findeco/views.py
nachtrag error handling