bump to CallMeterNG v2.3.20
remove custom language
Merge remote-tracking branch 'origin/cm2-translation' into cm2

Conflicts:
	res/values-nl/strings.xml
	res/values-pt/strings.xml
	res/values-sk/strings.xml
	res/values-tr/strings.xml
Merge remote-tracking branch 'origin/cm2-translation' into cm2
Merge remote-tracking branch 'origin/cm2' into cm2-translation
update translation stats