customized button rendering:
- whether to show them
- where to place them
slight refactoring of the form
handled submit action
added server-side update logic
added server-side validation and base for client-side validation
added to the model 'created' and 'updated' events
if there are errors they get attached to the model and rendered in the view
removed previous validation errors on a next update
made form cancel button working
form gets closed on crew updated event
new crew view gets wrapped into a form
made it working
fading out  and disabling a form on update and enabling it thereafter
added form submit on enter
implemented deletion of crew members (UI gets updated after a server responds)
refactored event triggering
added fade out effect to destroying vies