Cleanup of Avery US-Letter templates.

Cleanup of Avery US-Letter templates.

 - Spaced between manufacturer and part # to facilitate sorting, i.e. Assume part #s are 5 digits and right justified.

 - Unified descriptions so they are consistent with the generic portion of Avery's descriptions, and their are fewer unique descriptions to facilitate translations.

 - If multiple types per sheet or part #, the part # is suffixed with an appropriate description (e.g. 8391-Disc).

git-svn-id: https://glabels.svn.sourceforge.net/svnroot/glabels/trunk@317 f5e0f49d-192f-0410-a22d-a8d8700d0965