2010-01-21  john verzani  <verzani@john-verzanis-macbook-pro.local>

	* R/items.R: moved update_ui/enabled_when/visible_when out of
	items. They belong in containers, itemgroups.

2010-01-19  john verzani  <verzani@john-verzanis-macbook-pro.local>

	* R/base.R (next_method): new method for finding next method in parent environment

	* R/base.R (has_slot): mutatr method replacing exist(keu, envir-.)

	* R/itemgroup.R: added set_model method

