fix ls_alias for NetBSD as well

IPython/core/alias.py

@@ -69,8 +69,8 b' def default_aliases():'
                           # things which are executable
                           ('lx', 'ls -F -o --color %l | grep ^-..x'),
                           ]
-        elif sys.platform.startswith('openbsd'):
-            # OpenBSD 
+        elif sys.platform.startswith('openbsd') or sys.platform.startswith('netbsd'):
+            # OpenBSD, NetBSD 
             ls_aliases = [('ls', 'ls -F'),
                           # long ls
                           ('ll', 'ls -F -l'),