[NTVDM]

[NTVDM]
Changes in preparation for CORE-9773
- Split DosLoadExecutable into DosLoadExecutable & DosLoadExecutableInternal, the latter one can be used for small programs embedded in ntvdm.exe (will be used for integrated command.com).
- Factorize common loading code in DosLoadExecutable(Internal); just before starting a program, set the CPU registers to the default values DOS use; see comments in the code for more details (some programs expect those values).
- Set a correct termination type (hiword in the returned ErrorLevel) when terminating programs (the value is different for TSRs and for regular programs).
CORE-9773 CORE-9729 CORE-9711 CORE-8247

svn path=/trunk/; revision=68746