SFX Anywhere update v02 - BASIC support and optimised playback modes.

Hi.  I just added support for BASIC programs to the sound driver.  Most of the feature set is now available from BASIC using SYS and POKE commands.

Also a few new build options for the driver that can save some rastertime:

* Default to normal SID playback when only playing music and not using the mixer options: SID_IDLEOPTIMISED

* Raw mode using only normal SID playback: SID_RAWMODE

There is also the option to specify which order SID registers playback in, for music that requires a special setup: SID_FIXEDWRITELIST

See the included docs for more info on these changes.  Thanks.