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.
Partially split off the Logitech Serial Mouse emulation from Microsoft Serial Mouse;
Slightly reworked serial port emulation (the two UART's are now device_t's, non-FIFO mode implemented and is now default, FIFO mode reimplemented from scratch so it's now actually correct);
Added the emulation of the SiS 85c497 chip to the SiS 85c496/497 chipset;
Bugfixes to the emulated Super I/O chips and made them all device_t's now.
Bunch of improvements in the device, memory and MMU handling.
Re-worked the NEAT 286 chipset (ported from VARCem).
Re-worked the ATI 28800 a bit, added Sierra SC1502x ramdac to VGA Wonder XL (Compaq) since it supports such.
Top 384K memory handling improvements (256K top memory too)
Added MCA version of MPU-401 (not tested much, however).
Re-worked the SCAT 286 chipset.
Merged floppy.c and fdd.c and renamed floppy_*.c (the floppy image format handlers) to fdd_*.c;
Reading the AT or PS/2 keyboard controller status no longer clears the transmit timeout bit, fixes error 8601 (mouse error) on the IBM PS/2 Model 80;
MMU translate and DMA physical reads and writes now go through _mem_exec instead of directly to ram[], should fix the last remaining problems with remapped mappings;
Implemented the Sound gain dialog;
Added the resource for the "New floppy image" dialog and the needed functions for the functionality of exporting the currently mounted floppy image as 86F, both of which should be finished in the next commit;
Applied the CD-ROM fixes from the PCem commit;
Added the "Keep ratio" option for full screen stretch.
IBM.H is gone, video stuff re-organized. Keyboard stuff reorganized.
Machines that have their own video, mouse and/or keyboard now have all this in their machine file.
Fixed and other cleanups here and there.
