Remove the quiet mode flag (-q) from grep in version check commands
to ensure that their stdout output is visible.
While at it, switch the remaining regex matches (perl, sscep, awscli) to
fixed-string matching where appropriate, so that special characters in the
version string are matched literally.
For libzip, the zipcmp and zipmerge branches ran grep and then
unconditionally exited 0, so a version mismatch was never reported and
the version check override always passed.
Signed-off-by: Josef Schlehofer <pepe.schlehofer@gmail.com>