Restore the clisp build.

You guessed it right, it's the (declare (type)).
Remove SETUP-ENVIRONMENT VOP.

It doesn't do anything.
Move arg-verification before the arguments are butchered.
x86-64: use a single trap for arg count errors.
Provide a better warning for IGNORE in the wrong scope.

(lambda (x) (let () (declare (ignore x)))) now says
"IGNORE declaration for a variable from the outer scope: X"
instead of
"IGNORE declaration for an unknown variable: X".
The same deal for functions.

Closes lp#736383.
Provide a better error for (STRING not-string-designator).

The old "cannot be coerced" is misleading, since #(#\a #\b #\c) can be
coerced to a string, but isn't a string designator.
Just say "#(#\a #\b #\c) is not a string designator".

Fixes lp#1314767.
Report unused var errors when fopcompiling.

lp#492200