[Create/edit survey] Allow predefined or free-form data collection in a job, but not both

[gino-m]

Summarizing @n-clinton: Having both leads to confusion and complexity in the survey creation process. If users need both, they can create two jobs ,one with predefined, one with free-form.

[kenstershiro]

Agreed to start from hero use cases to capture these more accurately - discussion is quite abstract atm

[gino-m]

+1. It's not clear whether this or #1736 are needed. We need to nail down #2082 to be able to answer this.

[gino-m]

Counterpoint: multiple users have been confused by the "When adding a new site.." condition in the task list when setting up a new survey. If we require data collection jobs to be either structured (predefined) or opportunistic (free form), we would remove this complexity, while still leaving open the option of using two jobs to allow both types of data collection.

@vittorino @amegantz @rawbzz Any opinions here?