Merge pull request #1 from deib-polimi/master

Data collectors adapted to dc factory
Update the VM/App availability monitor
Update App availability monitor
Update metrics in ModacloudsMonitor class
updated available metrics to integer values
Merge remote-tracking branch 'upstream/master'
Bug fix
new version
Merge remote-tracking branch 'upstream/master'
bug fix
Merge remote-tracking branch 'upstream/master'
bug fix
bug fix
Merge remote-tracking branch 'upstream/master'
* bug fix