[IMPROVED] Allow for longer monitoring value strings
[ADDED] Error Code Array
[IMRPOVED] Error Notification Mail with new headers
[IMPROVED] Re-factored monitoring criticals/errors

* [ADDED] new monitoring method : endCronjob
* [IMPROVED] Use newly added error codes
* [ADDED] mail notifications, enabled by default
* [ADDED] cron disable on fatal errors with exit code != 0
* [ADDED] Command line swtich: -f = Force running crons even if disabled
* [ADDED] Disabled status in monitoring site

This will improve error handling in our cronjobs. Fatal errors now
require manual intervention by explicityly running crons with the force
option (`-f`). Until they are forced to run, crons will stay disabled.

Fixes #773 once merged
[FIX] Disable mail notifications on disabled crons
[IMPROVED] Added logging failed SQL queries to payouts
[FIX] Double error message in log
[IMPROVED] More testing of error handling, block class