Add scripts/clean

diff --git a/scripts/clean b/scripts/clean
new file mode 100755 (executable)
index 0000000..3a639f5
--- /dev/null
+++ b/scripts/clean
@@ -0,0 +1,14 @@
+#!/bin/sh -e
+
+if [ -d 'dist' ] ; then
+    rm -r dist
+fi
+if [ -d 'site' ] ; then
+    rm -r site
+fi
+if [ -d 'htmlcov' ] ; then
+    rm -r htmlcov
+fi
+if [ -d 'httpcore.egg-info' ] ; then
+    rm -r httpcore.egg-info
+fi