Move to nwbuild.sh to scripts/ folder
Add scripts/build_git.sh

This downloads and builds git from source
Support building git for 32 bits

This allows to have a wider compatibility on OS X
Default build_git.sh arch to x64
Add ./scripts/build_extras.sh

Downloads node and git to the extras/ folder so the desktop app can add
them to it’s path
Support importing extras in desktop app
Pass env variables to desktop/ide.html
Merge pull request #252 from FriendCode/feature/desktop_extras

Feature desktop extras