Added tests for interview_configuration blcok SCHOONER-506
Added tests for interview_configuration blcok SCHOONER-506

Extended the blockly_interpreter tests to make this happen.  Thanks,
@nbudin!

The interpreter for testing blocks by writing blockly dsl inline can now
put a set of variables in the execution context.  You can use variables_get
to read them.  This lets you test AR models that blockly operates on.

nbudin/blockly_interpreter,nbudin/blockly_interpreter,nbudin/blockly_interpreter,nbudin/blockly_interpreter