Merge pull request #118 from AM1729/datetime

compare on string

Author: moovida

gears/src/main/java/org/hortonmachine/gears/io/stac/HMStacItem.java

@@ -74,7 +74,7 @@ public static HMStacItem fromSimpleFeature( SimpleFeature feature, String sugges
         Object datetimeObject = feature.getAttribute("datetime");
         if (datetimeObject != null) {
             String dateCetStr = datetimeObject.toString();
-            if (dateCetStr != null) {
+            if (!dateCetStr.equals("null")) {
                 stacItem.dateCet = HMStacUtils.dateFormatter.parse(dateCetStr);
             }
         }