Move last remaining module from std.c

Since `std.c.windows.winsock` is so large, I modified the declaration finder in Dscanner to automatically search for all declarations in a given file from all files in a given directory, patch here:

https://gist.github.com/joakim-noah/a4ddc674a3c293d7d39a

Running it with this module and the druntime source found two symbols that are already defined in druntime, `ENAMETOOLONG` and `ENOTEMPTY` from `core.stdc.errno`, though they're set to different numbers.  It hits a bunch of false positives in `core.sys.posix.*`, but since this module is only defined for Windows, those shouldn't matter. I removed a reference to Windows from `core.sys.posix.time`.

To initially verify that this tool is working, I had it dump all declarations from the winsock module and manually checked that it found all 303 declarations.  I ran it against a copy of winsock.d, to make sure it hit all 303 from the original in the copy, and that checked out too.

Also corrected a documentation comment having to do with Android's TLS implementation, which I realized I had written up incorrectly.