o Add consts where appropriate.
o Rename some variables that were shadowing global declarations.
o Remove register storage-classes.
o Make errmsg a const, so we can just set error messages instead
of using sprintf/strcpy.
o Set WARNS=2
Reviewed by: bde, des
This will make a number of things easier in the future, as well as (finally!)
avoiding the Id-smashing problem which has plagued developers for so long.
Boy, I'm glad we're not using sup anymore. This update would have been
insane otherwise.
