Automate usage of Fonts by Bootstrap and Font-Awesome. Fixes #164.

Fixes #164.

Works on both `dist` and normal mode.

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Changes:
1. Added `Grunt` task `copy:fonts` that copies the Fonts from `<%= yeoman.app %>/bower_components/bootstrap-sass/dist/font/**` and `<%= yeoman.app %>/bower_components/font-awesome/fonts/**` to `<%= yeoman.app %>/styles/fonts/`
2. Added `copy:fonts` task to Grunt task `serve`. When passing the `dist` argument, it runs `copy` task with runs both `copy:fonts` and then `copy:dist` which will copy the fonts into `<%= yeoman.dist %>/styles/fonts/` directory.