New Feature: Differentiate between cancelled and "delayed" lineitems
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In the ACQ user interface, it is now more clear to users when a lineitem has
been fully cancelled or if it has been cancelled temporarily (e.g. back-
ordered).  

When a lineitem is cancelled, but "keep_debits" is true on the cancel reason,
the lineitem is in effect delayed instead of truly cancelled.  This is now
more obvious in the interface with different row styling for cancelled vs
delayed lineitems.  We also always show the lineitem cancel reason (label) 
next to the non-title attributes in the lineitem list display.