1207 Add client request heade to defaultDataStore.

Author: josebarrueta

impl/src/main/java/com/stormpath/sdk/impl/ds/DefaultDataStore.java

@@ -74,6 +74,7 @@
 import java.util.TreeMap;
 
 import static com.stormpath.sdk.impl.http.HttpHeaders.STORMPATH_AGENT;
+import static com.stormpath.sdk.impl.http.HttpHeaders.STORMPATH_CLIENT_REQUEST_ID;
 
 /**
  * @since 0.1
@@ -630,6 +631,11 @@ protected void applyDefaultRequestHeaders(Request request) {
                 request.getHeaders().setContentType(MediaType.APPLICATION_JSON);
             }
         }
+
+        List<String> clientRequestId;
+        if (headerMap != null && ((clientRequestId = headerMap.get(STORMPATH_CLIENT_REQUEST_ID)) != null)) {
+            request.getHeaders().put(STORMPATH_CLIENT_REQUEST_ID, clientRequestId);
+        }
     }
 
     protected CanonicalUri canonicalize(String href, Map<String,?> queryParams) {

impl/src/main/java/com/stormpath/sdk/impl/http/HttpHeaders.java

@@ -78,6 +78,8 @@ public class HttpHeaders implements MultiValueMap<String, String> {
 
     public static final String STORMPATH_AGENT = "X-Stormpath-Agent";
 
+    public static final String STORMPATH_CLIENT_REQUEST_ID = "X-Stormapth-Client-Request-Id";
+
     private static final String[] DATE_FORMATS = new String[]{
             "EEE, dd MMM yyyy HH:mm:ss zzz",
             "EEE, dd-MMM-yy HH:mm:ss zzz",