bttf

A command-line utility for doing datetime arithmetic, parsing and formatting. A non-exhaustive list of features: * Generate sequences of datetimes using RFC 5545 recurrence rules. * Perform calendar and absolute duration arithmetic interchangeably in a way that is safe with respect to daylight saving time. * IANA time zone database support. * The ability to tag arbitrary data in a JSON lines format with datetimes. This works great for reformatting or localizing timestamps in log files. * Datetimes can be written in a variety of flexible formats. For example, `bttf time fmt '5pm last thursday'`. * Compare and sort datetimes.