Twisted version scheme differs wether setuptools is installed or not

New submission from tarek <None>:

If setuptools is not installed, and if I build a trunk version using twisted setup script, I'll get a : "8.2.0+r27123" for the version number (cooked by twisted.python.versions.Version.short)

If setuptools is installed, it'll cook the version number and the output will differ
and will be "8.2.0-r27123".

The behavior should be the same,

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Type     : enhancement
Component: release management
Keywords : 
Priority : normal
Nosy     : 
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http://twistedmatrix.com/trac/ticket/3912