Update README.md

README.md

-CAS4 Overlay Template
+CAS Overlay Template
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-Generic CAS maven war overlay to exercise the latest versions of CAS 4.x line. This overlay could be freely used as a starting template for local CAS maven war overlays.
+Generic CAS maven war overlay to exercise the latest versions of CAS. This overlay could be freely used as a starting template for local CAS maven war overlays.
 
 # Versions
 ```xml