Remove std.traits.unsigned as scheduled.
Move along some overdue deprecations.
There's no point in scheduling deprecations anymore.

deprecate no longer generates an error, so we might as well just
deprecate directly.
fix property enforcement
Avoid multiple giant h1s in CONTRIBUTING.md
Merge pull request #2263 from 9rnsr/enforceProp

fix property enforcement
Update the Qt signals and slots link.
Merge pull request #2264 from ckakman/patch-1

Update the Qt signals and slots link.
Workaround for issue# 12961.
Merge pull request #2260 from jmdavis/deprecated

Move some deprecations along.