add volatile load/store to core.bitop
gc.config: updated comments, allow disabling command line processing, change environment var to DRT_GCOPT
Merge branch 'master' of https://github.com/D-Programming-Language/druntime into gc_config_cleanup
configure options at link time
[Refactoring] Reorder file names in MANIFEST and SRCS
[Refactoring] Gather common code in rt.util.typeinfo
fix Issue 13052 - TypeInfo.getHash should return same hash for different floating point zeros.
Move last remaining module from std.c and remove a reference to Windows in core.sys.posix
fix Issue 13661 - static array init does not call destructors

Add internal functions to handle assignment from an array with rvalue elements.
Extend unittest for ldexp()

The unit test checks some edge cases for 80bit reals.
This pull request adds a test for platforms which only have 64bit reals (e.g. ARM, PPC).
move drt_ variables to rt.config
add function drtConfigOption to retreive an option
show current settings in GC help message
Suppress ddoc highlighting of every occurrence of "memory" in the text.
Merge pull request #1008 from redstar/math

Extend unittest for ldexp()
Merge pull request #1007 from joakim-noah/move_winsock

Move last remaining module from std.c
use rt_ prefix instead of drt_, remove extern(C)
use naked asm blocks to clear registers
fix Issue 12800 - Fibers are broken on Win64

- save non-volatile registers RSI and RDI
Merge pull request #1012 from MartinNowak/fix12800

fix Issue 12800 - Fibers are broken on Win64
do not try to detach a thread that isn't running yet
Merge pull request #1016 from rainers/unittest_thread_detach

Fix unittest in core.thread