ios-webkit-debug-proxy description

Added description of how to install and use the ios-webkit-debug-proxy.
Updated cloning description

Tried to make it a bit clearer about what brew install does and simply installing the proxy manually.
Merge pull request #655 from snevesbarros/patch-1

ios-webkit-debug-proxy description
initial commit of the grid.md
Updated description for local grid config

Added a link to all grid properties description and updated description.
Update to the json config file

Updated the config file to make it clear about what to update.
cleanup

lined up the config file and removed blank lines.
Merge pull request #656 from snevesbarros/master

Local Grid setup documentation