Werkin M. Assoff 0.99.6

This release includes an enormous number of fixes to port-mapping and the Windows build, plus major enhancements to time-signatures. Time signatures can be inserted in the pattern editor and the event editor, and are shown in both. Port-mapping now detects when a configuration has changed since the last run and prompts the user for an optional remapping. In Windows, Seq66 seamlessly handles ports grabbed by the Microsoft MIDI Mapper. An embarrassing number of other bugs were found and fixed.