Import man pages from the MongoDB Manual (new docs) into Server

The Manual (formerly "the new docs") can and will generate man pages for all of the utilites (mongodump, mongo, mongorestore, et al) and other binaries (mongod and mongos) distributed with MongoDB. These man pages should be distributed with MongoDB for consistency and easy updating.

To generate these pages. Have Sphinx installed, clone the docs/ repo and run "make man". Alternately the "make build-man" will also gzip the man pages, if that's preferred.