Make improvements

- Fix build flakes
- Polyfill SIGWINCH on Windows
- Fix an execve issue on Windows
- Make strerror show more information
- Improve cmd.exe setup/teardown on Windows
- Support bracketed paste mode in Blinkenlights
- Show keyboard shortcuts in Blinkenlights status bar
- Fixed copy_file_range() and copyfile() w/ zip filesystem
- Size optimize GetDosArgv() to keep life.com 12kb in size
- Improve Blinkenlights ability to load weird ELF executables
- Fix program_executable_name and add GetInterpreterExecutableName
- Make Python in tiny mode fail better if docstrings are requested
- Update Python test exclusions in tiny* modes such as tinylinux
- Add bulletproof unbreakable kprintf() troubleshooting function
- Remove "oldskool" keyword from ape.S for virus scanners
- Fix issue that caused backtraces to not print sometimes
- Improve Blinkenlights serial uart character i/o
- Make clock_gettime() not clobber errno on xnu
- Improve sha256 cpuid check for old computers
- Integrate some bestline linenoise fixes
- Show runit process names better in htop
- Remove SIGPIPE from ShowCrashReports()
- Make realpath() not clobber errno
- Avoid attaching GDB on non-Linux
- Improve img.com example

libc/crt/crt.S

@@ -28,12 +28,21 @@
 //	@note	FreeBSD is special (see freebsd/lib/csu/amd64/...)
 //	@noreturn
 _start:
+
+//	Get startup timestamp as early as possible.
+//	Used by --strace flag and kprintf() %T.
+	rdtsc
+	ezlea	kStartTsc,bx
+	mov	%eax,(%rbx)
+	mov	%edx,4(%rbx)
+
 #if SupportsFreebsd()
 	test	%rdi,%rdi
 	cmovnz	%rdi,%rsp
 	jz	0f
 	movb	$FREEBSD,__hostos(%rip)
 #endif
+
 0:	mov	(%rsp),%ebx			# argc
 	lea	8(%rsp),%rsi			# argv
 	lea	16(%rsp,%rbx,8),%rdx		# envp