Add MeteringDeletate to Openstack Handle

Adds the ability to connect to Ceilometer through the openstack delegate.

https://bugzilla.redhat.com/show_bug.cgi?id=1129462
Allow non-wrapped openstack services

As Openstack evolves, there are likely to be new services we need to support.
This change will allow us to return the underlying Fog-based Openstack service
if we haven't yet wrapped Openstack service with a corresponding
tenant-supported Openstack Service Delegate class.

I'm a little torn on this commit, because the presence of a new Openstack
service should give us pause and require that we think about whether the service
needs to be restricted to tenant-based operations.

However, I also know how much the Openstack ecosystem changes and evolves.  So,
it makes sense to be able to simply pass through to the underlying service until
we absolutely need to wrap the service with tenant-based operations.

Associated with:
https://bugzilla.redhat.com/show_bug.cgi?id=1129462
Exclude Ceilometer from service fallback list

Be explicit in the fact that there is no service fallback for the Openstack
Ceilometer service.
Added require for miq_timeline

Added require for miq_timeline to fix an issue where timelines weren't drawing correctly.

https://bugzilla.redhat.com/show_bug.cgi?id=1117431
Merge pull request #385 from blomquisg/bz1129462-openstack-handle-metering

Bz1129462 openstack handle metering
Merge pull request #387 from h-kataria/require_miq_timeline_css_in_app_assets

Added require for miq_timeline
ManageIQ model infrastructure changes for vendor specific methods.

Changed Method class schema to add vendor specific methods and
relationships.
Added red hat and vmware pre provision and customize request methods.
Changed customizerequest and preprovision instances to call vendor
specific methods.
Changed VMProvision_Template and VMProvision_VM schema default values
to pass vendor name as message to pre provision and customizerequest.
ManageIQ model cloud changes for vendor specific methods.

Changed Method class schema to add vendor specific methods and
relationships.
Added amazon and openstack pre provision and customize request methods.
Changed customizerequest and preprovision instances to call vendor
specific methods.
Changed VMProvision_Template and VMProvision_VM schema default values
to pass vendor name as message to pre provision and customizerequest.
infra method changes