Merge branch '2.0-branch' of https://github.com/Pylons/deformdemo int…

…o 2.0-branch

Prep 2.0.14 release

Sync with Deform 2.0.13

Update widget docs per #226 for consistency across code examples

There is no trove classifier for PyPy3

Release 2.0.7 of deformdemo