Merge branch 'develop' into issue1364_TimedRotatingLogger

improve vector documentation (hardbyte#1420)

Bump release version

Fixblfgz still wasn't merged properly

Merge branch 'extra_args2' into 4.1.x-dev

Update logger.py

Print the unix time when the logger starts up.

fix broken badges

Add `dest` option to append argument

Clean up variable names, notes, etc.

Clean up comment after !1302 (hardbyte#1322)