Export-Feature and updated Readme

• Added Export-Feature as well as fixing for this feature.
• Included new Feature in Readme.
• Updated explanations in Readme and fixed some typos.
• Removed Work-In-Progress example generator, since this can easily be queried from the openEHR-Repo
• Added py-doc-strings to methods
• Set Default-Auth-Data for config.ini
• Allowed bat-files to present errors to the user