Support file globbing into a directory

[gwicksted]

Support compiling all .less files in a folder (with globbing) to a destination folder so each one does not have to be specified. Could also support collapsing a tree structure (as well as preserving relative paths by default).

This currently does not work due to dest being a directory.

less: {
    build: {
        files: [
            {
                cwd: ['Styles'],
                src: ['**/*.less'],
                dest: 'Styles' // or any other folder
            }
        ],
        options: {
            ext: '.css' // default
        }
    }
}