Added MessageValidationInvalidMetadata error

Author: BernardHarrison

injectionApi/src/main/java/com/socketLabs/injectionApi/SendResponse.java

@@ -189,6 +189,9 @@ public String getResponseMessage() {
             case InvalidTemplateId:
                 return "An invalid TemplateId was found in the message";
 
+            case MetadataOrTagsAreTooLarge:
+                return "Metadata and tags exceed 12.5KB";
+
             case TemplateHasNoContent:
                 return "The specified TemplateId has no content for the message";
 

injectionApi/src/main/java/com/socketLabs/injectionApi/SendResult.java

@@ -79,7 +79,9 @@ public enum SendResult {
     /** SDK Validation Error: Expected messageType of basic or bulk */
     MessageValidationInvalidCustomHeaders,
     /** SDK Validation Error: Message contains invalid metadata */
-    MessageValidationInvalidMetadata;
+    MessageValidationInvalidMetadata,
+    /** Metadata and tags exceed 12.5KB */
+    MetadataOrTagsAreTooLarge;
 
     /**
      * Convert a String into a SendResult enum