Added text_embedding example

Author: Chris Park

examples/text_embedding.curl

@@ -0,0 +1,7 @@
+curl -X POST \
+-H "X-RosetteAPI-Key: your_api_key" \
+-H "Content-Type: application/json" \
+-H "Accept: application/json" \
+-H "Cache-Control: no-cache" \
+-d '{"content": "Cambridge, Massachusetts" }' \
+"https://api.rosette.com/rest/v1/text-curl"