builder/parallels: Added some navigation keys in "boot_command". Fixes [GH-1442]

Enhancements for Parallels builder

We have to set either 'ostype' or 'distribution', but not both.

parallels: Support for Parallels Desktop 10

Fixed multiple VMware typos.

Allow specifying project for source images in GCE

Within GCE, images may be shared across projects. Prior to this
commit, there was no way to inform the GCE builder that a source
image belonged to a specific project. This adds an optional
'source_image_project_id' key to the GCE builder config.

fix panic when vagrant cloud response fails

Fix typo in docker builder docs

add disk size to google compute

parallels-iso: ISO not removed from VM after install [GH-1338]

Also remove floppy and prl-tools ISO if applicable.

website: typo in vagrant cloud 

Update GCE source_image in the docs

builder/googlecompute: rename "Gsutil" to "Gcloud" now that we're updating "gcloud" and not "gsutil".

Also renamed files accordingly.

builder/googlecompute: added support for all standard VM images

[GCE] google compute builder is broken, gsutil update fails in newer images

Do not re-add floppy disk files to VMX

This commit fixes errors like this in the vsphere post-processor when using floppy files in the builder step:
Error: File (/var/folders/zl/57c1vmr532z_ryf1scw53_b9ycmxh7/T/packer964492999) could not be found

The configure VMX step re-adds the floppy files, so we need to configure the VMX and _then_ clean the VMX in that order.

Added support to use templates for more fields in null-builder and amazon-builder