Return x_form_buttons to _content partial.
Return x_form_buttons to _content partial.

Previously the x_form_buttons where included rather non-intuitively
throught the pagination partials.
Now pagination partial are removed, but we still need the form buttons
so adding those directly.

ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic,ManageIQ/manageiq-ui-classic