Remove temporary debugging hack in verifier
Check that we don't have any "left over" pointers after walking the data section
Make root_node_num attr private
No need for $DataSectionStartMarkerSize variable in Reader role
Add debugging to the File writer
Clarify how search tree pointers to the data section work in the spec
Fix "MaxMind, Inc.." typo in LICENSE files
Tweak debugging message
Add _debug_sprintf to Debugs role
Lots of changes to the verifier

This fixes some bugs in the verification and adds more checks. It now checks
to see that every "top level" structure in the entire data section has a
corresponding pointer from the search tree, and vice versa (every data section
pointer corresponds to a top level item).
Add a small test that the verifier can verify files we build.

This doesn't catch bugs that occur with large files.
Clarify how data section separator size affects calculation of data section offset