* fix fstat wrong on darwin
* move std.debug.global_allocator to std.debug.global_allocator_state and make it private
* add std.debug.global_allocator as a pointer (to upgrade your zig code remove
the '&')
* standard library knows if it is linking against libc and will
sometimes call libc functions in that case instead of providing
redundant definitions
* fix infinite loop bug when resolving use declarations
* allow calling the same C function from different C imports.
closes#277
* push more logic from compiler to std/bootstrap.zig
* standard library provides way to access errno
closes#274
* fix compile error in standard library for windows
* add implementation of getRandomBytes for windows