advance coq version checking at configuration time

Author: ybertot

configure.ac

@@ -184,8 +184,8 @@ COQVERSION=$($COQC -v | sed -n -e 's|.*version *\(.*\)$|\1|p' )
 AC_MSG_RESULT($COQVERSION)
 
 case $COQVERSION in
-  8.1[^0-9]*|8.2[0-9]*|8.3[0-9]*|8.4[0-9]*|8.5[0-9]*|8.6[0-9]*|8.7[0-9]*)
-    AC_MSG_ERROR(AC_PACKAGE_NAME needs Coq version 8.8 or higher)
+  8.[[0-9]][[^0-9]]*|8.10*)
+    AC_MSG_ERROR(AC_PACKAGE_NAME needs Coq version 8.11 or higher)
     ;;
 esac