Bug#753772: Document the use of uversionmangle=s//+dfsg/ with repack

[IOhannes m zmoelnig]

Package: devscripts
Version: 2.14.6
Followup-For: Bug #753772

just to add my own 2¢:
"+dfsg" is not the only common extension for repacked sources.
personally i prefer "~dfsg" (adopted from the pkg-multimedia team), as
UPSTREAM~dfsg sorts before UPSTREAM, which is nice if upstream decides to
re-release a version with non-free parts stripped.

quick stats using grep-aptavail show:
   5276 +dfsg
    587 ~dfsg
    554 .dfsg
    192 -dfsg

thus: if you ever come up with a solution that adds a suffix to the upstream
version (and i would very much welcome such a feature), please allow for more
possibilities than just "+dfsg".

gfmsar
IOhannes