this documentation is so old, it borders on useless. Some of these files don't exist and many of them have been refactored and/or moved. Maybe when the dev team actually wants people to be able to help, they will take a moment to point people in the right direction.
See this reply :
Nodes currently only store the historical blockchain for serving out to newly initializing peers and for stats queries in the rpc. Since 0.8 the software is restructured so that it never accesses it otherwise, and the next release will likely include a feature to operate with only about 1GB storage.
I think they are trying to make it simpler.