[vcloud_director] Added support for deleting vApps.
Use ruby-style attribute setters in AutoScaling::Group initializer
Use old hash syntax to support older ruby versions
[vcloud_director] Implement vapp.destroy and get rid off vdc.delete_vapp
Merge pull request #2161 from faber/auto-scaling-group-initializer-bugfix

AutoScaling Group initializer attribute assignment
Merge pull request #2157 from rsalm/vcloud_director_delete_vapp

[vcloud_director] Added support for deleting vApps.