If the directory tree for used LLVM compiler is not from a LLVM source checkout and clang_version is not found, assume clang_version = llvm_version.
Disable the aliasbitcast.ll test for fastcomp, since it is invalid IR.
Update closure-externs.js

Add a gamepad support with closure.
Upstream changes to scons support from IMVU.
Added new test suite 'interactive', which contains those browser tests that require human verification in the loop. Move all such tests from 'browser' test suite to the 'interactive' test suite so that the browser test suite only contains automated tests.
Added a (currently failing) interactive test for SDL_WM_ToggleFullScreen.
show logging about preload/pre-main time even without a main
add docs and testing for mem init file being async
add commented out line to help debugging llvm opt aborts
mark opts in fuzz saves
Merge pull request #2198 from juj/interactive_tests

Interactive tests
Merge pull request #2195 from waywardmonkeys/upstream-scons-changes

Upstream scons changes
Merge pull request #2182 from juj/llvm_version

llvm_version check.
only include necessary system libraries amongst each other based on explicit dependencies; fixes #2191
add (void) to C functions in emscripten.h
move 'powered by' logo to media dir
provide a bitmap for the 'powered-by' logo
use png instead of jpeg for logos
remove extraneous eps since we have svg
only include necessary system libraries amongst each other based on explicit dependencies; fixes #2191