title: Coverting input to lowercase
body: <p>Hi i need to convert a text input and array into lowercase so when entered it can be matched against the array. I keep getting errors saying airline.Array.contains is not a function. Can anybody help please.</p>
  
  <pre><code>var euAirlines = [
        "British Airways",
        "Austrian Airlines",
        "Blue Islands",
        "KLM",
        "TAP Portugal",
        "Air Malta",
        "Air France",
        "germanwings",
        "Wideroe",
        "Lufthansa",
        "Aegean Airlines",
        "Citywing",
        "Flybe",
        "Aurigny",
        "airBaltic",
        "Swiss",
        "eurowings",
        "Croatia Airlines",
        "SAS",
        "LOT",
        "Air Serbia",
        "Iberia",
        "Wizz Air",
        "Blue Air",
        "easyJet",
        "Air Europa",
        "Czech Airlines",
        "Aer Lingus",
        "Eastern Airways",
        "Smart Wings",
        "Aeroflot",
        "Thomson Airways",
        "bmi regional",
        "Ryanair",
        "Monarch",
        "TAROM",
        "Brussels Airlines",
        "Jet2",
        "Meridiana",
        "Vueling Airlines",
        "CityJet",
        "Scilly Skybus",
        "Alitalia",
        "Thomas Cook Airlines",
        "Garuda Indonesia",
        "Norwegian",
        "Ukraine International",
        "Bulgaria Air",
        "Finnair",
        "Luxair"
      ];
  
      Array.prototype.contains = function (needle) {
         for (i in this) {
             if (this[i] == needle) return true;
         }
         return false;
      }
  
      var airlineInput = document.getElementById("airlineInput"),
        airlineArray = euAirlines.toString().toLowerCase();
      document.getElementById("claim-submit").onclick = function(e) {
        var lower = airlineInput.value.toLowerCase();
        console.log(lower);
        if (airlineArray.contains(lower.value)) {
  
         console.log("Match");
        }else {
  
          console.log("No Match")
        }
  
      }
  </code></pre>