Add v0.1 summary information

[zietzm]

Adds a notebook for computing release summary information and adds summary to the release notes.

Number of	Value
Drugs (≥ 1 exposure)	3,394
Adverse events types (≥ 1 occurrence)	17,552
Drug-event pairs	9,505,200
Significant* drug-event pairs	125,647
Drug-drug-event triplets†	222,155,888
Significant* drug-drug-event triplets†	5,729,992

* Significant determined by LOG(PRR) - 1.96 * PRR_error > LOG(2)

† This is not filtered by OFFSIDES, meaning a drug-drug-event triplet can be significant even if one of the drugs is more significantly associated with the event by itself.