[Dune] autobuild

[Christian Engwer]

Hi,

after 2 weeks without new autobuild logs I think I found the bug(s) :-)
The logs did not get stored in the database. I did some changes to
autobuild-store to make it more robust and fixed some smaller issues
in autobuild-client. I hope everthing will work now. I also updated
the scheduling policy of autobuild-qrunner. Now qrunnerhas a two stage
policy... if jobs are enqueued to "wait", than they are moved to
"trigger". In the next run the qrunner checks the no new job for the
same host entered "wait" and runs the job, or moves it to "trigger"
again.

The changes to the qrunner allow you to commit a series of patches
that will be checked as one big change. I.e. you change somthing in
common and therefore you need to change some parts of grid. If you
commit the changes to grid less then 10 min after the commits in
common autobuild will check against the latest version, including
_all_ changes.

Christian