Add redo-ifcreate to match djb's design.

I'm not quite sure why this needs to be a separate program, however, so I'm
probably not testing it correctly.

redo-ifcreate.py

@@ -0,0 +1,16 @@
+#!/usr/bin/python
+import sys, os
+import vars
+from helpers import *
+
+
+if not vars.TARGET:
+    sys.stderr.write('redo-ifcreate: error: must be run from inside a .do\n')
+    sys.exit(1)
+
+for t in sys.argv[1:]:
+    mkdirp('%s/.redo' % vars.BASE)
+    if os.path.exists(t):
+        add_dep(vars.TARGET, 'm', t)
+    else:
+        add_dep(vars.TARGET, 'c', t)