doc: add two more examples for servant projects

doc/examples.md

@@ -17,3 +17,21 @@
         A custom monad that can replace `IO` in servant applications. It adds among
         other things logging functionality and a reader monad (for database connections).
         A full usage example of servant/diener is also provided.
+
+
+- **[example-servant-elm](https://github.com/haskell-servant/example-servant-elm)**:
+
+	An example for a project consisting of
+
+  - a backend web server written using **servant-server**,
+  - a frontend written in [elm](http://elm-lang.org/) using
+    [servant-elm](https://github.com/mattjbray/servant-elm) to generate client
+    functions in elm for the API,
+  - test-suites for both the backend and the frontend.
+
+
+- **[example-servant-persistent](https://github.com/haskell-servant/example-servant-persistent)**:
+
+  An example for a web server written with **servant-server** and
+  [persistent](https://www.stackage.org/package/persistent) for writing data
+  into a database.