Note Encoding Implementation (dn-m#210)

* Factor out Kind decoding

* Add Note encoding implementation

* Add passing roundtrip test

* Add FIXME notes

* Fix formatting

* Add rountrip tests for Note

* Update linuxmain

* Use testRoundTrip syntax

Use tagged version of XMLCoder (dn-m#191)

Merge branch 'latest' of https://github.com/dn-m/MusicXML into latest

Remove @testable from tests (dn-m#151)

Add link to DTD