Fixes
- Roman 16 font characters were off by one pixel
- Added missing KFontCalc... and KFontMon... fonts
- gCLS should clear grey plane if applicable
- compiler: More descriptive error for undefined external variable
- DIALOG should error on an unterminated dCHOICE "..."
- Support IOOPEN("SND:") on Series 3
- compiler: Add support for # operator
- Support DTMF tones in SND: driver