Handle suspends

These are changes to handle suspend and resume events parsed from a carelink CSV file
Ah, v. clever ;)
I'm looking now (link: http://www.accessdata.fda.gov/cdrh_docs/pdf12/P120010c.pdf), as well as inspecting real data, and I disagree in my interpretation, and in fact I believe that all of `alarm_suspend` and the codes beginning with `low_glucose...` belong in the `low_glucose` reason category. LMK if you want to look at the data together.