[Mono-list] Small-medium project

[Miguel de Icaza]

I ran into an interesting class while trying to bootstrap the
mono-interpreter, the class is `System.DateTime'.  

For now I have just put a blank implementation (so I can get things
going).

It is a medium sized class, because it does a number of interesting
conversions from nanoseconds from the 1st of Jannuary of year 1.

Now, what makes this a non-trivial task is the fact that those
do not map directly to a calendar day.  They will do some jumping as
various calendar "standards" that we have had over the years.  So some
research needs to be put into this.

Not trivial, but definetly fun!

Miguel.