Remove MED synth and HMN tests from core player tests

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Remove unsupported note slide and persistent effect tests

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Remove unsupported Oktalyzer arpeggio and persistent effect tests

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>
Fix typo in Scream Tracker 3 type string

Signed-off-by: Claudio Matsuoka <cmatsuoka@gmail.com>