Avoid outputting any ANSI codes when color option is disabled.
Avoid outputting any ANSI codes when color option is disabled.

Previously, even with color output disabled, the pretty printer
for terms was putting ANSI codes like `^[[0m` around all identifiers.
(See GaloisInc/saw-script#957.)

GaloisInc/saw-script,GaloisInc/saw-script,GaloisInc/saw-script,GaloisInc/saw-script,GaloisInc/saw-script