Text tweak

A suggestion to smooth out the text -- if you think it's an improvement, happy to make a larger PR with all the instances of this fixed.
Need to check e.errno instead of os.errno. Fixes #8548
Merge pull request #8549 from gregdek/devel

Text tweak
Add some more notes about recent 1.8 developments to the changelog.
Merge pull request #8550 from sivel/issue/8548

wait_for module: check e.errno instead of os.errno. Fixes #8548
Remove duplicate compiling of task when: statements

Fixes #8538