tests: Move tests for executables to separate script

Move tests for xmllint shell and xmlcatalog to separate scripts and
enabled them in Autotools.

test/scripts/test.sh

@@ -0,0 +1,51 @@
+#!/bin/sh
+
+set -e
+
+echo "## Scripts regression tests"
+
+if [ -n "$1" ]; then
+    xmllint=$1
+else
+    xmllint=./xmllint
+fi
+
+exitcode=0
+
+for i in test/scripts/*.script ; do
+    name=$(basename $i .script)
+    xml="./test/scripts/$name.xml"
+
+    if [ -f $xml ] ; then
+        if [ ! -f result/scripts/$name ] ; then
+            echo "New test file $name"
+
+            $xmllint --shell $xml < $i \
+                > result/scripts/$name \
+                2> result/scripts/$name.err
+        else
+            $xmllint --shell $xml < $i > shell.out 2> shell.err || true
+
+            if [ -f result/scripts/$name.err ]; then
+                resulterr="result/scripts/$name.err"
+            else
+                resulterr=/dev/null
+            fi
+
+            log=$(
+                diff -u result/scripts/$name shell.out || true;
+                diff -u $resulterr shell.err || true
+            )
+
+            if [ -n "$log" ] ; then
+                echo $name result
+                echo "$log"
+                exitcode=1
+            fi
+
+            rm shell.out shell.err
+        fi
+    fi
+done
+
+exit $exitcode