Compatibility with pdfkit==0.6.1

[bctiemann]

ERROR: Cannot install django-pdfkit==0.3.1 and pdfkit==0.6.1 because these package versions have conflicting dependencies.

The conflict is caused by:
    The user requested pdfkit==0.6.1
    django-pdfkit 0.3.1 depends on pdfkit<=0.6.0 and >=0.5.0

To fix this you could try to:
1. loosen the range of package versions you've specified
2. remove package versions to allow pip attempt to solve the dependency conflict

I have to pin both django-pdfkit and pdfkit because pdfkit 0.6.1 fixes an important bug, but django-pdfkit only accepts up to 0.6.0. This results in a conflict that I can't resolve until it's fixed here.

[bctiemann]

Note that pdfkit 1.0.0 has been released, and it works fine with django-pdfkit. Please update the requirements in this package. Thanks!

[alexhayes]

I'd be more than happy to merge a passing pull request that makes this change but I don't have time to do this at the moment, sorry.

[bctiemann]

Is there any way I can submit a PR? I've tried to push a branch but github tells me I don't have write permission to this repo.