Additional documentation for the mud.

changelog.txt - Updates in the current version.
crashing.txt - Tips for recovering from crashes.
getting-started.txt - What to do when you start a new EmpireMUD.
license.doc - The EmpireMUD license.
update-* - Notes for upgrading from one version of EmpireMUD to another.
vnums.txt - An index of vnum blocks for included content.
