GET /api/city_search?q=<term> - search for something

  <search>
    <city>
      <country_code>GB</country_code>
      <name>London</name>
      <latitude>51.5</latitude>
      <url>http://www.dopplr.com/place/gb/london</url>
      <longitude>-0.116667</longitude>
      <geoname_id>2643743</geoname_id>
    </city>
    <city>
      ...
    </city>
  </search>  

  {
    "city":[
      {
        "country_code":"GB",
        "name":"London",
        "latitude":51.5,
        "url":"http://localhost:3000/place/gb/london",
        "longitude":-0.116667,
        "geoname_id":2643743
      },
      { ... },
    ],
  }