[feature] Support boot command for pvm builder

Similar to [GH-1082] but for parallels-pvm builder.
Parallels builder mistypes boot command on OmniOS

Fixes [GH-1185] and adds tests for the boot command.
Also requires the latest prl-utils (e592a15) to fix the stuck on enter
while typing.
Update GCE source_image to debian-7-wheezy-v20140415
Added documentation page for environmental variables. #1130
Changed the ordering of the environmental variables to be alphabetic.
Add option to enable enhanced networking (SriovNetSupport) for images.
Docs updated with new config option
Parallels errors while creating floppy disk GH-1225

Patch applied with modifications - tests updated to pass.
Parallels-iso errors while removing floppy drive GH-1226

Status "stopping" should be handled in IsRunning
Fixes #1244, Add a check for upload iso hash to ESXi Driver
post-processor/vagrant-cloud: initial commit
Update to CentOS 6.5
Improve the boot command sequence

Use a single command line, avoid the graphical installer, and use {{ .HTTPIP }} rather than the actual IP.
Also wait a bit before entering the commands to increase the chance of actually being in the boot menu.
Update the kickstart link

Instead of pointing at a specific (in this case actually non-working!) revision, point to the github UI for the
head revision.
The user is expected to find the 'raw' link there, but the page allows to also quickly look at changes etc, which
might be helpful for people unfamiliar with kickstart files.
Properly escape security_group_id to avoid markdown interpretation of the '_'
post-processor/vagrant-cloud: add api items
Merge pull request #1275 from ankon/docs-amazon-escaping

Properly escape security_group_id to avoid markdown interpretation of the '_'
Merge pull request #1278 from rickard-von-essen/issue_1225

Parallels errors while creating floppy disk GH-1225
Merge pull request #1279 from rickard-von-essen/issue_1226

Parallels-iso errors while removing floppy drive GH-1226
Merge pull request #1173 from rickard-von-essen/pvm_bootcommand

[feature] Support boot command for pvm builder