Add changes for music fast forward PR (#61)

This pull request allows my pull request InfiniTimeOrg/InfiniTime#1323 in the
InfiniTime project to build the simulator that's in this project. Both pull requests
add the feature that I requested here: InfiniTimeOrg/InfiniTime#1320

Co-authored-by: Dyllan Kobal <[email protected]>

Author: dyllan500

sim/components/ble/MusicService.h

@@ -56,6 +56,8 @@ namespace Pinetime {
       static const char EVENT_MUSIC_PREV = 0x04;
       static const char EVENT_MUSIC_VOLUP = 0x05;
       static const char EVENT_MUSIC_VOLDOWN = 0x06;
+      static const char EVENT_MUSIC_FORWARD = 0x07;
+      static const char EVENT_MUSIC_REWIND = 0x08;
 
       enum MusicStatus { NotPlaying = 0x00, Playing = 0x01 };