Merge pull request #29 from akushsky/master

Add global UUIDValueTransformer.

Author: hjacobs

src/main/java/de/zalando/typemapper/core/fieldMapper/UUIDValueTransformer.java

@@ -0,0 +1,23 @@
+package de.zalando.typemapper.core.fieldMapper;
+
+import de.zalando.sprocwrapper.globalvaluetransformer.annotation.GlobalValueTransformer;
+import de.zalando.typemapper.core.ValueTransformer;
+
+import java.util.UUID;
+
+/**
+ * Created by akushsky on 03.09.2015.
+ */
+@GlobalValueTransformer
+public class UUIDValueTransformer extends ValueTransformer<String, UUID> {
+
+    @Override
+    public UUID unmarshalFromDb(String value) {
+        return UUID.fromString(value);
+    }
+
+    @Override
+    public String marshalToDb(UUID uuid) {
+        return uuid.toString();
+    }
+}