Upgrade webview to the latest stable C version 0.1.1. Use Git submodules

[tuffnatty]

[francisl]

I tried your branch, but I can't make it run on os x.

I have a bunch of c/objc error. I not famillar enought with C to debug it. If you have some clues I can take a look.

edit: I removed the log pollution. You can find my discussion and solution here: https://forum.nim-lang.org/t/6771 I'll propose another fix that solve the issue with osx and new function name from 0.1.1 and forward.