Autocomplete textboxes about cropplanning HOT 6 OPEN

General support is in place and fairly straightforward.  It meshed well with the
existing setup.  Two "subissues" need to be addressed before this issue is 
resolved:

Issue 5.2:
The support needs to be spread through the rest of the code, though.  Enable
autocomplete on all text boxes where it should be enabled.

Issue 5.3:
Also, we need to create a way for these autocompletion lists to be updated.  As 
it
stands, the lists are not updated for new entries, even if the new entry is the 
box
in question.  This may be handled by a larger redesign to implement
"DataUpdateEvents" or something.  These lists could be updated on any 
"DataUpdateEvent.

DataUpdateEvents were implemented in PA2 release, so subissue 5.3 is done.  
si5.2 is
still valid since there are a number of fields that could have autocomplete 
added to
them.

A new subissue 5.4: should the drop down box be abandoned in favor of the 
simple, in
box autocomplete?  It certainly LOOKS nicer.