minor improvements of sprivers translation of release notes 1.2
Add missing quotes.
Prevent echo from adding a newline.

Otherwise, even with empty i18nspector output, we triggered !0 exit code, and
an empty line in the script's output.
Use quoting more consistently in check_po.sh.
Make check_po.sh `set -u' compatible, and then use it.
Use single quotes unless double quotes are necessary in check_po.sh.
Make it clear that check_po.sh's output and exit code are now part of its public API.
Merge remote-tracking branch '451f/spriver/news_v1.2'
Update calendar.