Changed cronjob hint and sending messages only on errors.
Upgraded to a up-to-date rspec version.
Don't connect to xmpp server if no change is found

If a xmpp server is configured and send option is used, a xmpp
client connection was created. This behavior is changed in that way,
that only a connection is created, when new marks or changes are
found.
Added  a palmful of rspec test.
Increased markify version to 0.2.2