Add a simple stats unit test that tests the existing library functions
isc_stats_ncounters, isc_stats_increment, isc_stats_decrement,
isc_stats_set, and isc_stats_update_if_greater.
We should drop the HISTORY file because it's confusing and the same
information is covered by the release notes for .0 releases (or at
least they should be).
Remove references to the HISTORY file, update the README to tell
people go look somewhere else.
This was written down in the outdated doc/dev/release documentation.
Since the rest of that file can go, add these steps to a separate file
and update it to current standards (e.g. use git commands).