OCaml date time reasoning library

Features:

• Reasoning over time intervals via timere objects/expressions, examples:

• Pattern matching time and intervals. These work across DST boundaries.

• Intersection and union

• Chunking at year or month boundary, or in fixed sizes

• Evaluate (sub)expressions with a different time zone (e.g. intersection of 9am to 5pm of Sydney and 9am to 5pm of New York)