Minor bug fixes + improvements

• Fixed bug when using the regionalschluessel parameter in retrieve_data()
• Fixed bug that leads keyring to fail when trying to retrieve the credentials on a Windows machine.
• Fixed bug with test_login()
• Allow to switch language between German and English.
• Allow to supply sachmerkmal and sachschluessel as parameter
• Increased default value to 25000 for the number of retrievable value labels via retrieve_valuelabel().
• Revised vignette / help files

First CRAN Release

1.2.0

Updated docs