Update model-mommy req

[orf]

Is there any reason it's pinned to 1.2.6? 1.3.2 is the latest I think, and this library ends up forcing us to use 1.2.6 :(

[codecov-io]

Codecov Report

Merging #44 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff          @@
##           master    #44   +/-   ##
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  Coverage     100%   100%           
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  Files           6      6           
  Lines         674    674           
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  Hits          674    674

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[stphivos]

Hey sorry about that!

I'm looking into the Travis build errors of the PR to be able to use model_mommy 1.3.2.

Also, since v1.3.2 is not backwards compatible with v1.2.6, it would be best to add support for a version range like we did for Django, so something like: model_mommy>=1.2.6,<=1.3.99, so it doesn't force it on others too.