Added style #15. Does this clarify REST?

15-restful/README.md

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+Style #15
+==============================
+
+REST = REpresentational State Transfer (http://www.ics.uci.edu/~fielding/pubs/dissertation/top.htm)
+
+REST is a style for network-based interactive applications that
+underlies the Web. The example here doesn't go over the network, but
+preserves the main contraints of REST, which are:
+
+- Interactive: end-to-end between an active agent (e.g. a person) and a backend
+
+- Separation between Client (user interface) and Server (data storage)
+
+- Statelessness, as in client--stateless-server: every request from
+  client to server must contain all the information necessary for the
+  server to serve the request. The server cannot store
+  context of the interaction. Session state is on the client.
+
+- Uniform interface: resources that are created and retrieved,
+  resource identifiers and hypermedia representation that is the
+  engine of application state
+
+Additionally, the networked style has the following contraints, not shown here:
+
+- Cache
+
+- Layered system
+
+- Code-on-demans
+
+Possible names:
+
+- RESTful
+- Stateless Ping-Pong
+