Add missing jshint dependency
Add missing jshint dependency

The `gulp-jshint` 2.0 package requires `jshint` to be installed manually.
junaidrsd/sc5-styleguide,SC5/sc5-styleguide,SC5/sc5-styleguide,patriziosotgiu/sc5-styleguide,varya/sc5-styleguide,patriziosotgiu/sc5-styleguide,soulfresh/sc5-styleguide,varya/sc5-styleguide,soulfresh/sc5-styleguide,junaidrsd/sc5-styleguide