Pull out common inventory sorting.
Create full stacks when combining pack. [1733]
Avoid spamming with combine messages.
Add PowerWyrm's fixes for do_ident_item(). [1037]
Remove extraneous parameter in do_ident_item().
Tidy up some format lines.
Merge pull request #279 from bensemmler/1733

Stacks are only merged when the pack is combined (this doesn't allow for partially picking up a stack from the floor or a shop), and fix bugs introduced with inventory sorting and identification.  Closes #1733 & #1037.