Gelencsér Szabolcs / circlestack

- disk remove with op view in vm detail
- still use old disk remove for removing disks from template
- also fix some resize code

Closes #262

we don't have FileField in this form so this won't change much

http://django-taggit.readthedocs.org/en/latest/forms.html#commit-false

- users without customize privilige can change name, also the form
  will validate correctly
- if we open it without modal, on error the modal will not be shown
  again

fixes #255

fixes #256

fixes #252