Optimize notify-*.sh even more. Use XDG_RUNTIME_DIR if available.

resolve many notifications issues

readme & changelog, release 1.0.10

release 1.0.9

Don't hide the terminal window from the taskbar

improve auto-generation & maintenence of messages.pot and *.po

remove more unused code

support vala 0.46 / ubuntu 20.04, fix debian/changelog, maybe

track dynamic current_highest_major-N instead of track static major v…

…ersion N and higher