Use AR relations to save fields/inputs and values

Instead of saving/destroying fields/inputs and values one at time
Use the Active Record relations to save these with a single save
call on the parent. This is done by adding the :autosave to the has_many
relations

It also includes the removal of to_i calls on the id fields. This will
help us when we switch to GIT and have strings as id's and the to_i
calls would fail. the to_i has been changed to to_s
Added gettext calls into PXE view
Added gettext calls into configuration view

Also rewritten some files from ERB to HAML
Merge pull request #979 from skateman/gettext-configuration

Added gettext calls into configuration view
Added missing 'forest_delete' route

https://bugzilla.redhat.com/show_bug.cgi?id=1163382
https://bugzilla.redhat.com/show_bug.cgi?id=1163384
Merge pull request #961 from mkanoor/pregit_controller

Use AR relations to save fields/inputs and values
Merge pull request #1017 from skateman/gettext-pxe

Added gettext calls into PXE view
Merge pull request #1046 from h-kataria/added_missing_route_forest_delete

Added missing 'forest_delete' route