In Nagios-Threshold.cs:

2013-01-29 -- Keith Olenchak:
-Converted class to hold threshold values for warning and crit, rather than relying on the program to keep track.
-Class initiation now requires both a warning threshold and critical threshold, either can be null but we throw an exception if both are null.
-ReturnCode enum made a public member of the namespace rather than the nagiosextentions class.
-Added error handling to parseThreshold to throw an exception if the threshold is marked with '@' but no range is defined with ':'.
-Finished checkThreshold()

In Program.cs:
2013-01-29 - Keith Olenchak:
-Added calculations for getting the delta, in minutes, between now and the age of the oldest file.
-Added getStatus function, converts ReturnCode enum value in to a string.
-Added buidOutput function to handle the final output to STDOUT, it builds the string based on the verbosity level.