0.46 release prep [ci skip]

Add changelog for 0.45.0

Update PR template with changelog link

Update changelog for 0.43.0 release.

Add changelog for 0.42.0

Closes mozilla-mobile#1944: Remove unneeded default arg of initWebView

Add changelog for 0.40.0

Add changelog entry for 0.39.0

Fix routes.statuses to be under the right decision tasks

Closes mozilla-mobile#1664: Use BrowserFragment.onCreateView instead …

…of onViewCreated.