Automate model restructure code adjustments.

Minor pathing adjustments and expose platform category to aid the
 cloud/infra navigation.
Add test for passing platform attributes to automate during provisioning
Initial pass of the Automate model restructure.
Fixed tree name being passed in x_build_node_id call.

Fixed to pass in correct tree name to x_build_node_id method, it was blowing up when logged in user didnt have access to :sandt_tree.

https://bugzilla.redhat.com/show_bug.cgi?id=1115717
https://bugzilla.redhat.com/show_bug.cgi?id=1117993
Fixed delete button on namaespace summary screen.

Delete namespace button on namespace summary screen was throwing an error, fixed code to delete correct record.
Merge pull request #123 from tinaafitz/automate_model_restructure

Automate model restructure
Merge pull request #173 from h-kataria/ae_namespace_delete_fix

Fixed delete button on namespace summary screen.
Merge pull request #177 from h-kataria/bz_1115717

Fixed tree name being passed in x_build_node_id call.
Simplify OpsController::Diagnostics#log_depot_build_edit_screen

https://bugzilla.redhat.com/show_bug.cgi?id=965889
Fix typo

https://bugzilla.redhat.com/show_bug.cgi?id=965889
Remove unnecessary verify and validate methods for log_depot_settings

https://bugzilla.redhat.com/show_bug.cgi?id=965889
Remove credential validation from creation

FileDepotNfs.create!(:uri => "nfs://test") fails because of missing credentials
https://bugzilla.redhat.com/show_bug.cgi?id=965889
Add #verify_credentials methods to appropriate FileDepot subclasses

https://bugzilla.redhat.com/show_bug.cgi?id=965889
Change FileDepot ::SUPPORTED_DEPOTS to #supported_depots

Build a hash of subclass => display_name for all descendants
https://bugzilla.redhat.com/show_bug.cgi?id=965889
Update drop-down to to get the correct uri_prefix based on the model

https://bugzilla.redhat.com/show_bug.cgi?id=965889
Add support_case and depot_name to the edit screen where appropriate

https://bugzilla.redhat.com/show_bug.cgi?id=965889
Add reverse relationship for MiqServer#log_file_depot

https://bugzilla.redhat.com/show_bug.cgi?id=965889
Create log_file_depot using relationships

https://bugzilla.redhat.com/show_bug.cgi?id=965889
Simplify all the things

https://bugzilla.redhat.com/show_bug.cgi?id=965889
Ensure that all FileDepots are subclassed

https://bugzilla.redhat.com/show_bug.cgi?id=965889