configure: display correct version for md5sum

The old code simply scanned for the first digit, then munched anything
after that. This didn't work for md5sum, as it would see the "5" and
treat "5sum" as the version instead.

This patch tweaks the algorithm so that it looks for a second
consecutive digit (or dot) after the first. Since "md5sum" has only one
digit, the new code skips over it as intended.

Author: lambda-fairy

configure

@@ -104,8 +104,8 @@ probe() {
         T=$(command -v $P 2>&1)
         if [ $? -eq 0 ]
         then
-            VER0=$($P --version 2>/dev/null | head -1 \
-                |  sed -e 's/[^0-9]*\([vV]\?[0-9.]\+[^ ]*\).*/\1/' )
+            VER0=$($P --version 2>/dev/null \
+                |  grep -o '[vV]\?[0-9][0-9.][a-z0-9.-]*' | head -1 )
             if [ $? -eq 0 -a "x${VER0}" != "x" ]
             then
               VER="($VER0)"