added collection/index option defaults to mongod and mongorestore

For #377

To `mongod` this adds:
 * `--setParameter=defaultCompression=METHOD` (zlib, other options are quicklz, compressed, lzma)
 * `--setParameter=defaultPageSize=SIZE` (4MB)
 * `--setParameter=defaultReadPageSize=SIZE` (64KB)
 * `--setParameter=defaultFanout=SIZE` (16)

These values are also gettable/settable through the `getParameter` and `setParameter` commands.

To `mongorestore` this adds:
 * `--defaultCompression=METHOD`
 * `--defaultPageSize=SIZE`
 * `--defaultReadPageSize=SIZE`