Update version to 1.6a1-dev.
Merge pull request #1133 from normanjaeckel/SplitMaster

Update version to 1.6a1-dev.
New API for widgets using a metaclass.

It is now possible to define a default state and to submit extra stylefiles and javascript files when defining a widget in an app. This is done by a new metaclass in openslides.utils.dispatch. Also fixed some other tests.
Merge pull request #1134 from normanjaeckel/NewWidgetAPI

New widget api