created if app and IfUser model
remove direct reference to TimtecUser
created custom signup form
working signup form, with validation
custom IfUser admin to edit added fields
remove all TimtecUser from core models
Merge branch 'master' into if-signup-3528

Conflicts:
	accounts/models.py
	if/models.py
merge issues
fix pep8; adds loginform example and signup completion stubs forms