Add Ken Silverman's INSTS.DAT bank format

[Wohlstand]

This is a bank format used to store banks for KSM songs.

Here is a small pack of KSM songs and the source code of KSM related things, sample music files and the specification in the "KSMFORM.TXT", found at here http://advsys.net/ken/download.htm: ksmsongs.zip