Use NLog for logging.

We really shouldn't reinvent the wheel, and a quick research on the web reveals that NLog is well written and among the existing logging frameworks the one that is probably the easiest to use...

See also issue #5 (closed).

For hints on how to limit the rate of emails being sent out by NLog, see the following blog posting:

• 5 Minute NLog Wrapper: Limiting The Number Of Emails Sent
• see snippet 12 for formatted versions of the code from the above blog post