Minimize memory allocation on new connection

There's a significant amount of memory allocated when a new connection is established solely to create the ReadOnlyProps. Need to figure out a way to minimize this. It looks like the majority of memory allocations occur in this org.apache.phoenix.util.ReadOnlyProps constructor:
https://github.com/apache/phoenix/blob/master/phoenix-core/src/main/java/org/apache/phoenix/util/ReadOnlyProps.java#L61

Another notable memory allocator is this java.util.HashMap.putAll call:
https://github.com/apache/phoenix/blob/master/phoenix-core/src/main/java/org/apache/phoenix/jdbc/PhoenixConnection.java#L192