Unify user_input data model for different configurations

[JGreenlee]

Background

There is an inconsistency in the structure of user inputs stored on the server, depending on whether the configuration is "MULTILABEL" or "ENEKTO", which we have been talking about unifying for a while. (This is concerning the user_input property of confirmed and composite trips.)

Current data model

Current structure of confirmed/composite objects:

MULTILABEL:	ENKETO:
{ ... "user_input": { "mode_confirm": "walk", "purpose_confirm": "exercise" }, ... }	{ ... "user_input": { "trip_user_input": { _id: ..., data: { name: "TripConfirmSurvey", xmlResponse: "<user response>", start_ts: ..., end_ts: ..., ... }, metadata: ..., }, ... }

Current structure of UserInputMap on the phone (since e-mission/e-mission-phone#1106):

MULTILABEL:	ENKETO:
{ ... "<tripId>": { MODE: { data: { label: "walk" } }, PURPOSE: { data: { label: "exercise" } } }, ... }	{ ... "<tripId>": { SURVEY: { _id: ..., data: { name: "TripConfirmSurvey", xmlResponse: "<user response>", start_ts: ..., end_ts: ..., ... }, metadata: ..., } }, ... }

Proposed Change

Proposed structure of confirmed/composite objects

MULTILABEL:	ENKETO:
{ ... "user_input": { mode_confirm: { _id: ..., data: { label: "walk", start_ts: ..., end_ts: ..., ... }, metadata: ... }, purpose_confirm: { _id: ..., data: { label: "exercise", start_ts: ..., end_ts: ..., ... }, metadata: ... } }, ... }	{ ... "user_input": { TripConfirmSurvey: { _id: ..., data: { name: "TripConfirmSurvey", xmlResponse: "<user response>", start_ts: ..., end_ts: ..., ... }, metadata: ... }, ... }

Proposed structure of UserInputMap on the phone:

MULTILABEL:	ENKETO:
{ ... "<tripId>": { mode_confirm: { _id: ..., data: { label: "walk", start_ts: ..., end_ts: ..., ... }, metadata: ... }, purpose_confirm: { _id: ..., data: { label: "exercise", start_ts: ..., end_ts: ..., ... }, metadata: ... } }, ... }	{ ... "<tripId>": { TripConfirmSurvey: { _id: ..., data: { name: "TripConfirmSurvey", xmlResponse: "<user response>", start_ts: ..., end_ts: ..., ... }, metadata: ... } }, ... }