Bug 616697 - string "Payment rec'd..." should be more cleared. (in taxinvoice.scm)

[Frank H. Ellenberger]

Hi Chris, 

could you have a look at https://bugzilla.gnome.org/show_bug.cgi?id=616697 ? 
"rec'd" is a somewhat ambiguous abbreviation.

Also the strings used in the options should be displayed translated (_ ... ).
(N_ ) is a dummy macro used for strings in array declarations, which later 
should be called by (_ ).

Frank