Merge pull request #18 from boudewijn-tribler/dimitra-master

Fixes.
Merge pull request #19 from boudewijn-tribler/dimitra-master

Typo: now uses memory database for barter.db.
Merge pull request #20 from boudewijn-tribler/dimitra-master

Order activity by time and more debug output.
for vu
Merge remote-tracking branch 'remotes/dimitra/master' into dimitra-master