Measure and log Pystone performance, and - if possible - CPU type

Pystone performance will give an indication of the performance that can be expected from SAB, par2 and unrar
Scheduling logging in proper format (hh:mm), so 08:05 instead of 8:5

Old:
2014-10-26 08:03:11,305::DEBUG::[scheduler:127] scheduling speedlimit(['5000']) on days [1, 2, 3, 4, 5, 6, 7] at 8:5

New:
2014-10-26 08:18:45,493::DEBUG::[scheduler:127] scheduling speedlimit(['5000']) on days [1, 2, 3, 4, 5, 6, 7] at 08:05
Support for the NZB meta field "x-rating-host".
Update text files for 0.7.20RC1
Merge pull request #184 from sanderjo/0.7.x

Measure and log Pystone performance, and - if possible - CPU type
Merge upstream