[Halld-offline] data challenge configuration

[Mark M. Ito]

As an example of what I meant as subversion directory for keeping 
condition information for the data challenge, see

 
https://halldweb1.jlab.org/data_challenge/01/conditions/data_challenge_1.html

Note the instructions at the bottom for how to check out the page and 
the files. You should try it. It illustrates the concept.

Note also that, at this writing, the information is far from complete. 
For example, there is no control.in yet.

The html file serves as documentation both for versions and commands but 
also for the configuration files in the same directory (i. e., the 
html-file-containing directory).

We can then use subversion to keep ourselves in synch across the various 
efforts. Kind of a poor man's gridmake.

Why not use gridmake? We should discuss that. Maybe for data challenge 2?