Adding hierarchy to the filestore directory structure

[Shanti Subramanyam]

Currently, the filestore is a single flat layer with all files both 
pre-loaded and those that are generated during a run going into the same 
directory. As the number of users are scaled, this directory is unwieldy 
- I'm sure some of you may have tried to do a 'ls /filestore' and then 
cursed yourself for doing it !

How about using one directory for every 100 users or so ? Something 
similar for events ? Not sure how we'll deal with the added events and 
files during a run though.

Thoughts ?

Shanti