Django 1.7 / Mezzanine 4 support

[spookylukey]

It looks like mezzanine-blocks basically works with Mezzanine 4.0. However, really it should switch to using Django 1.7 native migrations.

Given that Mezzanine 4 has dropped support for Django < 1.7, I'd recommend not trying to release a version that supports both Mezzanine 3 / Django < 1.7 and Mezzanine 4 / Django 1.7+.

I guess doing this would depend on first addressing #14 . You could then add another version that was Mezzanine 4 / Django 1.7+ only. Would you accept a pull request for this?

[renyi]

A pull request would be nice, thank you. :)

[spookylukey]

I was thinking that #14 should be addressed first - so that compatibility concerns can be indicated, noting specific releases which are actually available.