Add back setting controls lost in the refactoring canvas (gh-3772)

Bump orange-canvas-core requirement to >=0.1.3

Revert "Fix for crash on empty data, better handling on sparcisity changes"

This reverts commit 246795b9bc2c343d4214cf42a986f2a6be40b732.

Fix for empty data crash, better handling of sparse data


Merge remote-tracking branch 'origin/owsave' into owsave

... due to rtfd/CommonMark-py#134

* Split requirements into sensible files.
* Have setuptools-git manage package data.
* Dev versioning incudes build date.
* Python 3.4 minimum requirement.
* ...