Add emscripten_async_wget2 with progress callback

Send request Post & Get with progress callback
Add sample HTTP using emscripten_async_wget2
Add comment,test,authors. Change indentation and comma space

Modify the indentation
Add Author
Add comment
Add test inside runner.py
Merge remote-tracking branch 'wolfviking/incoming' into incoming

Conflicts:
	AUTHORS
	src/library_browser.js
	system/include/emscripten/emscripten.h