Add disclaimer of warranty and limitation of liability

mmdebstrap

@@ -11,6 +11,14 @@
 #
 # The above copyright notice and this permission notice shall be included in
 # all copies or substantial portions of the Software.
+#
+# The software is provided "as is", without warranty of any kind, express or
+# implied, including but not limited to the warranties of merchantability,
+# fitness for a particular purpose and noninfringement. In no event shall the
+# authors or copyright holders be liable for any claim, damages or other
+# liability, whether in an action of contract, tort or otherwise, arising
+# from, out of or in connection with the software or the use or other dealings
+# in the software.
 
 use strict;
 use warnings;