[Ohrrpgce] SVN: teeemcee/7925 Fix wrong scripterr messages for bad item handles: add valid_menu_item_h

[subversion at HamsterRepublic.com]

teeemcee
2016-04-07 03:27:46 -0700 (Thu, 07 Apr 2016)
332
Fix wrong scripterr messages for bad item handles: add valid_menu_item_handle

Previously a bad menu item handle would result in a very inappropriate
"bad menu handle -1" [sic] error.

Also improved error display in "find menu item caption".

Removed valid_menuslot, valid_menuslot_and_mislot, and
find_menu_item_handle_in_menuslot.
---
U   wip/docs/plotdict.xml
U   wip/scriptcommands.bas
U   wip/scriptcommands.bi