pylightning: bump version number.

We should add this to the release checklist!  It was last changed
for version 0.7.1.

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

contrib/pylightning/lightning/lightning.py

@@ -5,7 +5,7 @@ from math import floor, log10
 import socket
 import warnings
 
-__version__ = "0.0.7.3"
+__version__ = "0.0.7.4"
 
 
 class RpcError(ValueError):