bumpversion replaces LF with CRLF on Windows

[jaraco]

In trying to employ bumpversion for the comtypes project, I found that on a Windows host, running bumpversion will create a large diff, replacing Unix newlines with Windows newlines.

Bumpversion should retain the newlines of the original file.

[jaraco]

I fixed this issue for the CPython reindent script at one point. I'll see if the fix there is applicable here.

[peritus]

This will be part of the upcoming version 0.5 — which you can install by running

sudo pip install https://github.com/peritus/bumpversion/archive/master.zip#egg=bumpversion-dev

I'd appreciate any testing before the release. Please note the new configuration format (documented in the README)