SL-20109: Big clean up. Now supports arbitrary mix of folders and entries for both items and textures. Better logging output

SL-20109: Hacked in some code to write thumbnails now - had to change the ID i saved for the texture from the object ID to the asset ID and then it worked for 3 test items.  Next up, tidy up the code, remove hacks and do a run on a local copy of the main SENRA inventory

SL-20109: now lets user copy a list of items or list of folder of items, copy a list of texture of list of folders of textures, then combine them and find matches by name - saving each match with the name, item ID and thumbnail texture ID - next is actually writing the thumbnails

SL-20109: display the inventory item asset ID and associated thumbnail ID (broken - all null UUID - for tomorrow)

First commit of code to investigate how we might do bulk uploads of inventory item thumbnails - both from a code and a UI perspective

# Conflicts:
#	indra/llui/llfolderviewitem.cpp
#	indra/newview/llinventorymodel.cpp
#	indra/newview/llinventorymodelbackgroundfetch.cpp

following promotion of DRTVWR-580

SL-19966 Reverted "SL-18721: Faster viewer shutdown time since performance improvements can lead to perceived inventory loss due to cache corruption"

This reverts commit cf692c40.

Don't try to select something if we are waiting for an item

when folder was recreated into stock fodler