- textarea: added attribute "autosave"
- set autosave attributes in text_fields, when "multiple_lines" was specified.
- remove for the time being "hkey" from "non_cached_instance_var_patterns",
since this was recently fixed (TODO: check regression test and reactivate it later)
- new Externally callable method: autosave-attribute:
this is a simplified version of "save-attributes", but which does
NOT perform input validation, which might be a problem in case of partial input
- add "autosave-attribute" to all policies, where "save-attributes" was set