Version 2.3: Support for CCLI Song Format and Metadata

After testing and further development, version 2.3 can be released.

Improvements:

• Support of the CCLI songselect format
• Support for Metadata which can be displayed dynamically during the song
• Improvements in source code
• Preparations for further development in source code, abstractions
• Bugfixes in displaying the songs

As always, I am looking forward to feedback, suggestions and bug reports.
Thank you!