Offsets test
Don't infinitely recurse in strtof().
select function: return error condition when network connection fails
remove stray console.log
Move error check into canRead function and use an outer scope variable to report the error condition.
- added test cases for select error reporting
- added missing error reporting for sockets in the write file descriptor set
Re-instate _ATTRIBUTE() usages.

These were broken because the definition of _ATTRIBUTE() from
libcxx was different, so change the libc definition and usage
to match.

Fixes issue #992.
Node issue 1669 was fixed and these tests work.
test_mmap works with Node now.
Clean up lists of files, building libcxx / libcxxabi.
Update to current libcxx.

This doesn't work yet as it needs to be customized for use with
emscripten still.
update libcxxabi.
Remove unused makefiles.
Build libcxx and libcxxabi with C++11.
Get things working with the new libcxx / libcxxabi.
Bump version.
Get exceptions working as they were before.

This no longer uses headers from libcxxabi and
in fact uses libcxxabi a bit less than before.

This no longer lets some new C++11 stuff such as
exception_ptr work as the support for that relies
upon libcxxabi code.
remove symbol removing hack; export all malloc symbols as weak; add test for a case where symbol removing made us not merge llvm constructors properly
test fixes
Merge pull request #986 from caiiiycuk/offsets_test

SDL mouse offsets test