Mina configuration is shared between endpoints

Establishing a MINA endpoint with a custom codec, and then establishing another without a custom codec is a problem. The second endpoint inherits the first endpoint's codec.

My recommendation is to not share configuration data between endpoint creation. I recommend that the MINA component instantiate a new configuration for each new endpoint instead of copying the previous configuration.

As a workaround the user can specify "codec" as a URI parameter with no value.