Update build task to overwrite nodewebkit.options.platforms array.
Initial config array is overwritten with an array of platforms as detected by parseBuildPlatforms.
Update README to reflect platform names as understood by grunt-node-webkit-builder.
grunt-node-webkit-builder doesn't understand `mac`.
Simple typo fix.
Merge pull request #213 from krainboltgreene/patch-1

Simple typo fix.
Typo fix
Add git rev to about dialog
Merge pull request #210 from OnAzureWings/specify_release_build_platforms

Fix specifying build targets