fix glGetString and eglQueryString, and optimize emulated glGetString
Merge pull request #1740 from waywardmonkeys/boost-libcxx-libc-interaction

Fix an issue with Boost compilation.
Merge branch 'master' of github.com:icetooth/emscripten into incoming
small whitespace style fix
put assertions in performance-sensitive code behind ASSERTIONS flag
optimize scanString to not run the regex more than once
bump js minifier name limit, and optimize to not create all the names on smaller inputs
updated library_sockfs.js to make WebSocket a local var and updated library_browser.js to modify requestAnimationFrame to provide a fallback to setTimeout if window is undefined
use doubles in makeBigInt
use asm ffi coercing for floats in load abort calls
cast to double before float in function pointer wrappers
use double for emscripten_get_now, to not lose precision from performance.now etc.
simplify wrapper asm coercions
handle vector types in calcAllocatedSize
clean up simd code, fix uint32x4 heap offsets, and add testing
ensure a dot in large float32 constants
fix uitofp of i64 to float32
improve fasta float32 testing
add test for precise float32 support, allow 3 modes of precise float32 support, and rename option to PRECISE_F32 to be consistent with other precision options
add asm1f test mode