Zurich lambda polling code

[matthewberryman]

My thoughts as code (and comments) on bringing in Zurich data as per urbanriskmap/riskmap#32
Note that this includes a more recent and substantive example of data under zurich/test/zurich_example.json
This also starts to address #7 although to fully address that for all Lambdas here I need to refactor things a bit—I know what to do exactly just ran out of time as that also requires some work in Jenkins build scripts and Jenkins configuration. One nice side benefit of using serverless for these is that you can define your rates as code.

[matthewberryman]

@talltom I've done some further work on Zurich (around environment variables and documentation) in the new serverless branch for this repo, along with the refactoring towards #7 - a little bit messy but made more sense to keep those changes together.
Suggested workflow:

1. Review and merge Zurich schema and fns (fns need work) cognicity-schema#16
2. Review and merge feeds API for Zurich cognicity-server#17 after Merge dev to form v3.0.0 release cognicity-server#18
3. Review this code and push to this branch if necessary.
4. I will then merge any changes into my serverless branch and test the Zurich code from here along with Qlue changes, and if the Zurich code works I will close & merge this pull request and then merge serverless branch into master after testing both (unless you want to review that in which case I will open a pull request). These step will also require some work in jenkins.