added username to users
added username autocomplete when editing talks
created invite user test on events
Merge branch 'master' of github.com:tasafo/palestras-coletivas
Merge branch 'master' into username

Conflicts:
	spec/integration/event/create_event_spec.rb
	spec/integration/talk/edit_talk_spec.rb
rake task to generate user names
fixed username generation report
Merge branch 'felipeik-username'