Backlog/112 alarms

Adds an Alarm document, finishing the issue https://github.com/telefonicaid/fiware-connectors/issues/112

It also adds new INFO traces needed by the alarm system.

A minor fix in the README has been done as well.
Considering the rule for alarm deactivation... Could it happen that a Bad context data at MySQL get wrongly disabled ater gettnig a INFO Persisting data for CKAN. How the log processing subsystem could avoid such situations?

(Probably my explanation above is not clear... in that case, let's move to skype :)