WIP: Add query and graphs for sub responses

[dgarros]

For the multi choices question, I wanted to explore what other responses were given along the responses that was getting the biggest number of responses

For example, for configuration generation and deployment, ansible was mentioned by 60% of the participants but what else are they using along with ansible.

This PR add some new query functions to easily query all answers provided with another answer.

For now I generated a new graph for each multi choice question which doesn't always make sense, I need to clean that up