Format code.
Rename quiz_node_relationship.parent_nid => quiz_node_relationship.quiz_qid
quiz_node_relationship.parent_vid => quiz_node_relationship.quiz_vid
More format.
Issue #54: quiz_node_relationship => quiz_relationship.
Issue #54: quiz_node_results => quiz_results.
Issue #54: quiz_node_result_options => quiz_result_options.
Issue #54:

- {quiz_node_relationship}.child_nid => {quiz_node_relationship}.question_nid
- {quiz_node_relationship}.child_vid => {quiz_node_relationship}.question_vid
Issue #54:

- {quiz_node_relationship}.qnr_id => {quiz_node_relationship}.qr_id
- {quiz_node_relationship}.qnr_id => {quiz_node_relationship}.qr_id
Issue #54: Add description for quiz_relationship.qr_pid column.
Issue #54: Fix SQL error
misc on HookEntityInfo
Add some more description for quiz_results's columns.
+ Description for {quiz_result_options}.{nid, vid}