Fixed PC speaker sound volume in PIT mode 0;
A few CPU emulation clean-ups;
Hard disk controller changing redone in a less messy way;
Re-added the long-missing key send delay handling to the XT keyboard handler;
Fixed a bug that was causing SLiRP not to work when compiled with MingW/GCC 7.3.0-2 or newer;
Some serial mouse and port fixes;
A lot of changes to printer emulation, mostly based on DOSBox-X;
Printer PNG writer now uses statically linked libpng;
Added support for the HxC MFM floppy image format and upped 86F format version to 2.12;
Ported various things from PCem and some from VARCem;
Added the S3 86c801/805 emulation (patch from TheCollector1995);
Fixed and renamed the EGA monitor options;
Better synchronized the 808x to the PIT and the CGA;
Fixed the CGA wait state calculation;
Cleaned up some things in mem.c;
Fixed some things in the floppy emulation to make VisiOn get the correct errors from the copy protection disk;
Fixed several renderer-related bugs, including the SDL2 renderer's failure to take screenshots;
The Jenkins builds are now compiled with MingW/GCC 7.4.0-1 and include all the required DLL's.
Several bug fixes;
Preliminar addition of the SDL 2 renderer (does not yet work correctly in full screen mode);
SCSI devices no longer have configurable LUN's (this matches the configurability of real SCSI devices);
SCSI LUN's are now handed by the device's handler;
Removed all unused strings;
Removed some unused code files;
Significantly rewrote the bus mouse emulation.
The settings dialog now keeps track of MFM/XTIDE/ESDI/IDE channels and SCSI ID's and LUN's;
The IBM PS/2 Model 50 now installs a Model 80-style memory expansion card (MCA ID FCFF) when more than 2 MB RAM is selected, and now supports a maximum of 10 MB RAM.
Re-worked the system pathnames (pc.c), renamed cfg_path to usr_path.
Other small things here and there.
Logitech bus mouse re-worked, should be OK now.
