Times often converted to UTC time (same time but lose UTC offset information)

[trevorld]

• Times are often converted to UTC time. Same time but we lose original time zone information.
• I was seeing bugs when trying to convert times with UTC offsets to POSIXlt() objects if I didn't set tz = "GMT".
• To preserve UTC offset we may need to write a custom datetime class? Or just keep everything a string?

[trevorld]

We've written a new datetime object package: {datetimeoffset}