MIPS specific linux constants

- core.sys.posix.fcntl
- core.sys.posix.signal
- core.sys.posix.sys.mman
- core.sys.posix.sys.socket
port back GDC's __jmp_buf for ARM/PPC/PPC64

- I rechecked glibc's definitions
__jmp_buf for setjmp
ucontext_t
stat_t
Revert "Merge pull request #208 from alexrp/remove-threadasm"

This reverts commit f66067edc21777106e39f16e30eae3b28cc4b156, reversing
changes made to c97b1e9074321f3aa9ea42cd7e91711ac6055e46.
fix noexecstack assembler flag

- "clang -cc1as" only accepts the double dashed version
merge GDC changes to threadasm.S
fiber_switchContext for MIPS_O32
add threadasm.S to win64.mak MANIFEST
fix copy&paste error in comment
Merge pull request #384 from dawgfoto/fixComment

fix copy&paste error in comment
Unify AA value alignment to size_t.sizeof (fixes bug 8583)

Sets the alignment of values in both AA declarations (object and aaA)
to size_t.sizeof bytes, which fixes byValue range iteration on x64.
Implement issue# 9337: There's no Duration.max.

Added Duration.max and Duration.min.
Added TickDuration.max and TickDuration.min.
Some tweaks to Duration's documentation.

It erroneously mentioned addYears and addMonths as functions on
std.datetime.Date.
Merge pull request #387 from jmdavis/time

Implement issue# 9337: There's no Duration.max.
bt() is no longer a builtin
Merge pull request #388 from WalterBright/15

bt() is no longer a builtin
Merge pull request #385 from dnewbie/master

Win32/Win64 compatibility