[john] - updated README
[NicoPaez] - Capybara config modified to run tests on Jenkins
[john] - external activity events endpoint
[john] - external action taken rule
[john] - added 'activity' to external_activity_events table

Allows us to store action_taken as well as action_created events in the table.
[john] - annotated new field
[Nícolas] - make compatible with mysql 5.6
[john] - external action created rule

Conflicts:
	db/schema.rb
[Nícolas] - Remove rspec-instafail and change rspec to documentation format

Conflicts:
	Gemfile
[john] - creators of an external action are also signers of the action
[Nícolas] - Fix some warnings
[john] - external action rule (combines external action taken and external action created rules)
[john] - schema and Gemfile.lock updates
[Nícolas] - Add ExternalTags and ExternalActions models. WIP ExternalActivityEvents#create to create external tags and action

Conflicts:
	db/schema.rb
[Nícolas] - WIP ExternalActivityEvents#create
[Nícolas] - Add a new context 'when there is an invalid external action' to ExternalActivityEvents#create tests
[Nícolas] - Add associative table between external actions and external tags
[Nícolas] - Add external_action_id to external_activity_events and remove duplicate columns between external_actions and external_activity_events
[Nícolas] - Remove duplicated columns between external_actions and external_activity_events
[john] - removed unused external action filters.