update appTasks coffeescript excerpt to match lineman ~0.34.2

Hi!  Thanks for putting lineman together, it's working quite well so far.

This is a super boring update--basically just synchronizing the docs with the current appTasks config. I pulled the definition straight from `lineman config` like so:

```bash
$ lineman --version
0.34.2

$ lineman config appTasks
{
  "common": [
    "coffee",
    "jshint",
    "handlebars",
    "jst",
    "concat_sourcemap",
    "copy:dev",
    "images:dev",
    "webfonts:dev",
    "pages:dev"
  ],
  "dev": [
    "server",
    "watch"
  ],
  "dist": [
    "uglify",
    "cssmin",
    "copy:dist",
    "images:dist",
    "webfonts:dist",
    "pages:dist"
  ]
}
```