Chris Shoemaker's patch: Comments and tweaks for gnc-component-manager.

[Derek Atkins]

Log Message:
-----------
Chris Shoemaker's patch: Comments and tweaks for gnc-component-manager.

	* gnc-component-manager tweaks
	  - Warn if we approach design limitation of component manager
	  - pass GUID as const in gnc_gui_get_entity_events, change
	    prototype, callers, and docs
	  - Clarify comments about receiving events after entity life-cycle

Tags:
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gnucash-gnome2-dev

Modified Files:
--------------
    gnucash:
        ChangeLog
    gnucash/src/app-utils:
        gnc-component-manager.c
        gnc-component-manager.h
    gnucash/src/doc/design:
        component-manager.texinfo
    gnucash/src/gnome-utils:
        dialog-query-list.c