Update readme.txt

Author: sriniadhiwork

documentation/training/nist-training-videos/readme.txt

@@ -1 +1,14 @@
 
+
+These videos were created when the infrastructure was hosted by NIST.
+Since it has been migrated to SITE - some of the server names referenced in these videos may not be extant and need to be
+appropriately adjusted. A rough guideline is as follows -
+
+edge.nist.gov --> ttpedge.sitenv.org
+hit-testing.nist.gov ---> ttpds2.sitenv.org
+hit-testing2.nist.gov --> ttpds.sitenv.org
+https://edge.nist.gov/ett --> https://ttpedge.sitenv.org/ttp
+
+Optionally,
+
+hit-dev.nist.gov  --> ttpedgedev.sitenv.org