i18n: all resource files in WEB-INF/i18n are now used
Merge remote-tracking branch 'idgis/i18n-multiple-basenames' into i18n-additions
message files split into multiple files
Merge branch 'i18n-additions' into i18n-codeTranslation

Conflicts:
	admin/src/main/webapp/WEB-INF/i18n/messages.properties
	admin/src/main/webapp/WEB-INF/i18n/messages_nl.properties