Revert "Closes now GroovyClassLoader."

This reverts commit 78640f1ad1c587b6518d795e131e4efebfc4a80c.
Merge branch 'master' of github.com:micromata/projectforge-webapp
Layout.
setTimeZone and setLocale return this for chaining.
clone() returns now DateHolder instead of Object.
Clone added.
getDays(), MonthHolder(int, int) added. Locale.GERMAN removed.
Locale.GERMAN must now be set.