Add more feature development partitions

[micahjsmith]

A feature development partition describes a set of inputs for a data scientist to focus on in engineering features in this project. For example, the set of all questions asked during Wave 1 of the survey is a partition.

If you think of a partition, then please create a new issue using the New feature development partition issue template. Afterwards you and anyone else can "claim" the partition by commenting me to indicate that you are working on it.

Here are some example partitions: #27 #30