The test program format randomly generates WiredTiger files with
different size objects and then does single-threaded operations
on those files.  The goal is to test the WiredTiger file formats.

format should be compiled with a version of Berkeley DB (which it
uses to verify format's results).  Create a link "db" in the
build_posix directory that links to the top-level of a Berkeley DB
distribution directory which contains a configured and compiled
build_unix subdirectory.