Change logo width in README

Updated logo size in README from 140 to 200 pixels.

Author: michaelzhao820

README.md

@@ -1,5 +1,5 @@
 ## OGO ##
-<img src="images/ogo_logo.png" width="140" />
+<img src="images/ogo_logo.png" width="200" />
 
 Object Graph Programming (OGO) enables manipulating the JVM heap declaratively through queries. The queries 
 are written using the [Cypher Query Language](https://neo4j.com/developer/cypher/). OGO supports two high-level