new version of CSD thick client

Some people requested some data from CSD, as it turned out it was ~22k GMTI files. Our CSD Thick client (filepuller app) was not working correctly, so I made some changes that (I hope) will make it work better. I've changed the way y which the BQS query string is read from the configuration file, it wasn't dealing properly with strings that included special (> < etc.) characters.

Also, I've added command line argument checking routine (now we are using two parameters, one for alternate config file and the other for "dry-run" option, one that does perform the query but does not download the files. The organisation of FilePuller class changed slightly: I have moved some parts of the code to separate methods (for better control over error handling). The main() function was also moved from FilePuller.cc to separate file (this is I think better to separate calls to the objects from classes themselves).

I will post the new version of filepuller app on the portal shortly.