TST: add some simple tests

tests/test_library_builders.sh

@@ -4,4 +4,13 @@ export BUILD_PREFIX="${PWD}/builds"
 rm_mkdir $BUILD_PREFIX
 source library_builders.sh
 
-build_openssl
+function surpress {
+    # Suppress the output of a bash command unless it fails
+    /bin/rm --force /tmp/surpress.out 2> /dev/null
+    $* 2>&1 > /tmp/surpress.out || cat /tmp/surpress.out
+    /bin/rm /tmp/surpress.out
+}
+
+suppress build_openssl
+suppress build_libwebp
+suppress build_szip