Bug 124228

To create an external binding for an existing service (e.g. BP, other BC) in CASA generally involves
- copying the WSDL manually into CASA (separate issue 124222)
- dragging & dropping a binding in CASA
- Knowing exactly where to go to change the default porttype reference to the copied WSDL 
- Knowing exactly where to go to change some address details
- Potentially needing to manually go navigate to the generated WSDL and edit manually

This requires very in-depth knowledge or WSDL and our tooling even to achieve simple tasks.

The alternative of using WSDL wizard generates a more usable WSDL, but:
- Is not what user expects to use in CASA
- still requires some manual interventions in WSDL and/or casa, e.g. to set an address

The work-flow should be as follows: 
1. User drags binding in CASA
2. A binding specific wizard is presented which allows users to reference an existing service (WSDL) or create a new 
one, and guides the user though filling in the connection details
3. CASA can either auto-resolve if there is only one service with that same interface, or give the user a choice of 
hooking up to any compatible service

It should also be possible to re-visit this guided view to change the configuration.