test-revert: display the list of all generated cases

This will help to track all existing cases.

(still very simple now)

tests/test-revert.t

@@ -460,7 +460,9 b' Write the python script to disk'
   > content = []
   > for filename, ctxkey, wckey in combination:
   >     cc = ctxcontent[ctxkey]
-  >     if target == 'base':
+  >     if target == 'filelist':
+  >         print filename
+  >     elif target == 'base':
   >         content.append((filename, cc[0]))
   >     elif target == 'parent':
   >         content.append((filename, cc[1]))
@@ -477,6 +479,11 b' Write the python script to disk'
   >     f.close()
   > EOF
 
+check list of planned files
+
+  $ python gen-revert-cases.py filelist
+  modified_clean
+
 Script to make a simple text version of the content
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