Document the API methods we'll need. Updates #46, Updates #87

docs/API.rst

@@ -0,0 +1,18 @@
+Converse.js API
+===============
+
+Done:
+-----
+
+* initialize 
+
+TBD:
+----
+
+* log in
+* log out
+* open a chat box
+* close a chat box
+* toggle a chat box
+* change user's presence status
+* change user's custom message