added information about clear_datastore flag in templates, and fixed documentation on keyname/group flags
Merge pull request #282 from shatterednirvana/specify-clear-datastore-in-templates

added information about clear_datastore flag in templates
not using -1 to -1 when authorizing security groups, because it silently fails to work
Merge pull request #283 from shatterednirvana/not-using-minus-one-in-sec-group

not using -1 to -1 when authorizing security groups, because it silently fails to work
fixed typo in disk name
Merge remote-tracking branch 'org/testing' into use-persistent-disks-in-gce
added missing docstring