[form fields] nicer behaviour of the password field: don't put internal field value on edition (triggering validation error if one validation without removing the value, due to confirmation mismatch), and don't show the field as required in such case

minor cleanup: don't use builtin 'id' as variable name

[forms/inline] fix #703911: add new link disappears if inline box removed. Since we've the information, we must specify the target type else we get random cardinality on ambiguous relations