Change-Id: Ia8588aeaad8b44a6a306d7d5bfecc895adde1910

This lets us run bssl speed at least. bssl client is currently compiled
out until we clean up our socket story on Windows and get it working.

Change-Id: Ib1dc0d0e0a6eed7544207e7bbe138503731fda67
Reviewed-on: https://boringssl-review.googlesource.com/2103
Reviewed-by: Adam Langley <agl@google.com>

Change-Id: I3da1af62de9a94317fa7f14fda00e230b32bf5d5
Reviewed-on: https://boringssl-review.googlesource.com/2081
Reviewed-by: Adam Langley <agl@google.com>

Change-Id: I4ea02a41ed614047ecda156d0c572b04baa174e6
Reviewed-on: https://boringssl-review.googlesource.com/1852
Reviewed-by: Adam Langley <agl@google.com>

Configures the SSL stack to log session information to a BIO. The intent is to
support NSS's SSLKEYLOGFILE environment variable. Add support for the same
environment variable to tool/client.cc.

Tested against Wireshark 1.12.0.

BUG=393477

Change-Id: I4c231f9abebf194eb2df4aaeeafa337516774c95
Reviewed-on: https://boringssl-review.googlesource.com/1699
Reviewed-by: Adam Langley <agl@google.com>

Apart from the obvious little issues, this also works around a
(seeming) libtool/linker:

a.c defines a symbol:

int kFoo;

b.c uses it:

extern int kFoo;

int f() {
  return kFoo;
}

compile them:

$ gcc -c a.c
$ gcc -c b.c

and create a dummy main in order to run it, main.c:

int f();

int main() {
  return f();
}

this works as expected:

$ gcc main.c a.o b.o

but, if we make an archive:

$ ar q lib.a a.o b.o

and use that:

$ gcc main.c lib.a
Undefined symbols for architecture x86_64
  "_kFoo", referenced from:
    _f in lib.a(b.o)

(It doesn't matter what order the .o files are put into the .a)

Linux and Windows don't seem to have this problem.

nm on a.o shows that the symbol is of type "C", which is a "common symbol"[1].
Basically the linker will merge multiple common symbol definitions together.

If ones makes a.c read:

int kFoo = 0;

Then one gets a type "D" symbol - a "data section symbol" and everything works
just fine.

This might actually be a libtool bug instead of an ld bug: Looking at `xxd
lib.a | less`, the __.SYMDEF SORTED index at the beginning of the archive
doesn't contain an entry for kFoo unless initialised.

Change-Id: I4cdad9ba46e9919221c3cbd79637508959359427

Change-Id: Iae1d12a25184261fef175b39e5dbc84afb1c006c