- Rename CD track files to proper names

- Rename CD track files to proper names
- Add meoblast001's track as track 10 "beast of insanity"
- Make silvercity use that track
- Make menu use cd track $menu_cdtrack
- Make intermission use cd track $sv_intermission_cdtrack (set on server; if empty, no track change is done when the scoreboard comes)

Only numbered CD track references left are the maps' mapname.cfg files. Should or should not get changed, not sure.

git-svn-id: svn://svn.icculus.org/nexuiz/trunk@3690 f962a42d-fe04-0410-a3ab-8c8b0445ebaa