update to llvm 3.4 ; 1.27.1
Merge branch 'incoming' into merge-3.4

Conflicts:
	emscripten-version.txt
Implement fflush for stdout and stderr. #2770.
Add test for fflush behavior.
Merge branch 'incoming' of github.com:kripken/emscripten into incoming
Merge pull request #2771 from juj/implement_fflush

implement_fflush
fix quoting in EXPORTED_FUNCTIONS examples; fixes #3007
update site news
fix SDL.setPannerPosition; update to 9cad24b06
fix some small issues found by closure compiler (IE incompatibilities)
Merge pull request #3012 from NWilson/smallfixes

fix some small issues found by closure compiler (IE incompatibilities)
There is no support for binary program in WebGL2.
Merge pull request #3014 from djg/webgl2-no-binary-programs

There is no support for binary program in WebGL2.
Disable fflush() introduced in https://github.com/kripken/emscripten/pull/2771 , since it breaks std::cerr printing in multiple parts. Update the test_fflush test to showcase this.
make clang version checking more robust; fixes #3011
Correct comment: memset -> memcpy.
[GL] Allow others to register GL contexts.

This makes it so that other users of emscripten can register a
context without having to copy/paste this body of code.
[glfw] Fix glfw3 test.

Can't call Int32Array constructor without new, so just use a regular
array like other code does.
Merge pull request #3019 from waywardmonkeys/gl-changes

[GL] Allow others to register GL contexts.
Merge pull request #3017 from waywardmonkeys/fix-memcpy-typo

Correct comment: memset -> memcpy.