bug 4211: more fixes to suggestion letter template handling

bug 4211: more fixes to suggestion letter template handling

* Now displays the correct list of fields to choose
  for suggestion letters.
* Clean up mixture of old and new column selection code
  introduced in commit 88bb1b63, thereby restoring
  the intent of the patch for bug 3522.
* Enable suggestion library to be used in suggestion
  letter templates

Signed-off-by: Galen Charlton <gmcharlt@gmail.com>
(cherry picked from commit 994d6e2aac6092b7c852546eeca2253f59270e53)

Signed-off-by: Chris Nighswonger <chris.nighswonger@gmail.com>