TEIIDDES-1966 Resolves several issues with VDB Editor multi-source binding panel

- Resolves layout issue - bottom portion of multi-source table was not taking all available space.
- Resolve issue with VdbSourceInfo class.  Internally was storing the VdbSource objects in a HashMap keyed on source name.  The Map keys were getting out of sync with the objects when user changed source names.  Converted to use List instead of a Map
- Resolves problem with Delete and Add - if user was inline editing the translator or jndiName, the buttons did not do anything even though enabled.