clone_template has sane defaults for all providers

This is for smoke-testing templates on every provider, so making clone_template
as provider-agnostic as possible was needed.

Additional resulting changes:
- EC2 mgmt backend is able to deal with image names as well as AMIs, much as it does
  with instance names and IDs
- destroy_vm seemed generally useful, so it lives in utils.providers now
- minor cfme_data template changes, reflected in private yamls
Avoid deleting providers tests to not mess the other tests
Tests to automate button and button group to catalog item
Merge pull request #966 from sshveta/catalogcustombutton

Catalogcustombutton
added wait_for ssh before configuring db

Seen a issue on jenkins where the IP comes back but ssh is not quite
there and it ultimately kills the job.  Added a wait_for
Merge pull request #1061 from dajohnso/wait_for_ssh

added wait_for ssh before configuring db
random ids in the idlist break everything
workaround for enabling internal db on 5302
Merge pull request #1062 from dajohnso/wait_for_ssh

workaround for enabling internal db on 5302
Fix snapshot tests to not 'splode
Merge pull request #1059 from mfalesni/avoid-deleting-providers-bz

Avoid deleting providers tests to not mess the other tests
Merge pull request #1057 from psav/fix_snapshot

Fix snapshot tests to not 'splode
Add missing return statement
Merge pull request #1065 from jkrocil/fix-appliance-build-datetime

Add a missing return statement
Reporting tests needed to have some VMs to work
Merge pull request #1066 from psav/fix_report_test

Reporting tests needed to have some VMs to work
Performance improvements to function_trace
Added pxe fields for Vsphere
Merge pull request #1069 from psav/fix_pxe_prov

Added pxe fields for Vsphere
Don't let exception bubble up from Pretty (even if obj's getattr is
broken)

Also fix wrong pretty_attr name