Auto-killing processes, somce changed code in the plaintext function and speed issues in network

Several days ago I had huge problems with the cron and the queue job that seemed to work endlessly. To analyze this, I added some logging possibility.

Additionally I added some code that kills queue, poller or cron when it is called again and the previously called job still runs and had run for at least 9 minutes. This value isn't changeable by now, since the time after which the job really is killed depends upon the time the poller.php is called in the cron. When it is called only every 30 minutes then these jobs can run for 30 minutes before getting killed.

Additionally I moved some code in the plaintext functions. At the moment I'm working at the export connectors and realized that I can use these functions for rich text exports (like the tumblr export) as well.

And the last change: My network view really slowed down. The reason: There are many contacts in my database. So I changed the query to force mysql to a faster query order.