Implemented cookie-based authentication to the API.

Created timestamper module to start the application.
Added cookie-based authentication to ts_api.
Added utility methods to ts_api:
    * make_json_400/1 and make_json_400/1
    * make_json_401/1 and make_json_401/2
    * parse_json_body/1 reads a JSON object from a HTTP request body.
Implemented ts_api_session module to manage api user sessions.
Fixed ts_entry:list* methods to be 0-indexed.
Removed the ts_json:ejson_to_record/1 implementation for ts_user records.
    Decided that ts_user records are never trusted from the client,
    manipulation of fields such as pwd, username will be restricted to
    app pages.
Changed the password hashing algorithm. Now uses SHA1(pwd + 256bit salt).
    Want to use bcrypt, investingating cross-platform bcrypt implementation.
Fixed yaws.conf config file.

src/ts_entry.erl

@@ -50,7 +50,7 @@ when is_integer(Start) and is_integer(Length) ->
 
     % return only the range selected.
     % TODO: can we do this without selecting all entries?
-    lists:sublist(SortedEntries, Start, Length);
+    lists:sublist(SortedEntries, Start + 1, Length);
 
 list({Username, Timeline}, StartDateTime, EndDateTime, OrderFun) ->