Provide __str__ implementations for Client Objects

[flyingsilverfin]

Problem to Solve

The client would be more user friendly and faster to interactively work with if all of the classes defined provide a nice __str__() representation. For instance, a Concept being printed would show its base type and ID (local information) rather than a memory address, Answers could print the concept maps/list/sets and explanations in string format, transaction could show the type, session could show the keyspace etc.

Current Workaround

Manually print out by calling specific methods to retrieve desired information

Proposed Solution

• Implement __str__() to print object contents better

Additional Information

[alexjpwalker]

This was implemented as one of the enhancements for Client Python 2.0 in #133 .