The command code 71 patch

THE 'PAGE-IN DISCIPLE' SUBROUTINE
This is called by using 'command code' 71. On return the DISCiPLE is paged-in and
the HL register contains 1, to indicate that this is a DISCiPLE.

136B PATCH      POP  HL                  Drop 'HOOK_RET' return address.
136C            LD   HL,#0000            Clear 'D_ERR_SP'.
136F            LD   (#0296),HL
1372            INC  HL                  Signal 'this is a DISCiPLE'.
1373            RET