Enlarge Connection Pool

Previously, the connection pool was the same size as the number of threads on
a system.  This change updates that value to double the number of threads on a
system so that there is some potential for single-thread connection
concurrency in all systems, especially in systems with only a single thread.

[resolves #606]

Author: nebhale

cloudfoundry-client-reactor/src/main/java/org/cloudfoundry/reactor/_DefaultConnectionContext.java

@@ -65,7 +65,7 @@ abstract class _DefaultConnectionContext implements ConnectionContext {
 
     @Value.Default
     public Integer getConnectionPoolSize() {
-        return PoolResources.DEFAULT_POOL_MAX_CONNECTION;
+        return 2 * PoolResources.DEFAULT_POOL_MAX_CONNECTION;
     }
 
     @Override