scripts/bench: add nobench option -n

The nobench option serves to report on previously collected benchmark
results. It calls QUAVIVER/BENCHMARK:REPORT instead of running any
benchmarks.

It requires SBCL.

* scripts/bench: Parse -n option, setting nobench variable
appropriately. If nobench is set, call QUAVIVER/BENCHMARK:REPORT and
exit.
(nobench): New variable.

scripts/bench

@@ -11,6 +11,7 @@ set -o nounset
 set -o pipefail
 set -o errexit
 
+nobench=
 tag=
 verbose=
 
@@ -104,6 +105,10 @@ while test "$#" -gt 0; do
     shift
     break
     ;;
+  -n)
+    nobench="nobench"
+    shift
+    ;;
   -t)
     if test "$#" -lt 2; then
       printf >&2 "bench: missing argument for option: %s\n" "$1"
@@ -126,6 +131,15 @@ while test "$#" -gt 0; do
   esac
 done
 
+if test -n "$nobench"; then
+  command sbcl --noinform --disable-debugger \
+    --eval '(require "asdf")' \
+    --eval '(asdf:load-system "quaviver/benchmark")' \
+    --eval '(quaviver/benchmark:report)' \
+    --eval '(uiop:quit)'
+  exit
+fi
+
 if test "$#" -le 0; then
   for implementation in abcl ccl clasp ecl sbcl; do
     if command -v "$implementation" >/dev/null; then