+ Add version info to Win2K add/remove.

+ Fiddle vrbls so Win2K add/remove can display version w/o future manual
  script fiddling.
+ Break apart the mysterious wizard-generated Win2K "Edit 3 Registry Keys"
  script items by hand into 3 separate items, so you can see what the heck
  they're doing in the script view.
+ pydoc.pyw was a problem:  it's installed by both the Main and Tools
  components.  So when both were selected, the second time it got
  installed Wise figured it was overwriting a pre-existing version, and
  made a backup copy in BACKUP.  A rollback-uninstall then restored that,
  leaving the Tools/Scripts/ directory non-empty, and so Wise couldn't
  remove that directory (or any above it).  Fixed by installing pydoc.pyw
  at most once.
+ Rearranged and commented the "register file extensions" section, because
  it was confusing and needs more work:  turns out it's not true that
  Win2K requires Admin privs to register file extensions, BUT, if you
  don't have Admin privs, Win2K requires a new way to register file
  extensions, and a way that doesn't blow up but doesn't do any good either
  on earlier Windows flavors.  I think I know how to get this done, but am
  too depressed to do it right now <0.7 wink>.