Add DateTime parser

[jbatte47]

Approaches to investigate:

1. Static list of formats to accept in DateTime.TryParseExact -- could come from config (or anywhere)
2. Regex parser
3. Regex-driven format selector

[chrislwade]

What is the method being added and do you some example use cases? I ask because there's already a DateTime.TryParseExact, although it only supports format strings.

[jbatte47]

I was actually thinking of a new interface / class: IDateTimeParser / DateTimeParser. Not sure about the method name. That'll probably just be parse, but I'm open to suggestions.