Add executable to make running directly from source easy

diff --git a/cura b/cura
new file mode 100755 (executable)
index 0000000..22133cf
--- /dev/null
+++ b/cura
@@ -0,0 +1,3 @@
+## cura
+#!/bin/sh
+PYTHONPATH=. /usr/bin/python ./scripts/linux/cura.py "$@"