Changed record keys to use lists instead of atoms.

Using atoms will not scale in the large. Also, using atoms as keys forced the
API to convert arbitrary end-user input to atoms, adding another potential
drain of the finite atom-space available.

- ts_api: url paths are now treated and matched as lists, not atoms.
  Usernames and API calls all use lists now.
- ts_json: key items (username, timeline ids) are now expected to be lists,
  not atoms.

src/ts_json.erl

@@ -7,10 +7,11 @@ encode_record(Record) -> lists:flatten(json:encode(record_to_ejson(Record))).
 
 record_to_ejson(Record=#ts_user{}) ->
     {struct, [
-        {id, atom_to_list(Record#ts_user.username)},
+        {id, Record#ts_user.username},
         {name, Record#ts_user.name},
         {email, Record#ts_user.email},
-        {join_date, encode_datetime(Record#ts_user.join_date)}]};
+        {join_date, encode_datetime(Record#ts_user.join_date)},
+        {ext_data, Record#ts_user.ext_data}]};
 
 record_to_ejson(Record=#ts_timeline{}) ->
     % pull out the username and timeline id
@@ -18,8 +19,8 @@ record_to_ejson(Record=#ts_timeline{}) ->
 
     % create the EJSON struct
     {struct, [
-        {user_id, atom_to_list(Username)},
-        {id, atom_to_list(TimelineId)},
+        {user_id, Username},
+        {id, TimelineId},
         {created, encode_datetime(Record#ts_timeline.created)},
         {description, Record#ts_timeline.desc}]};
 
@@ -32,15 +33,15 @@ record_to_ejson(Record=#ts_entry{}) ->
 
     % create the EJSON struct
     {struct, [
-        {user_id, atom_to_list(Username)},
-        {timeline_id, atom_to_list(TimelineId)},
+        {user_id, Username},
+        {timeline_id, TimelineId},
         {id, EntryId},
         {timestamp, encode_datetime(DateTime)},
         {mark, Record#ts_entry.mark},
         {notes, Record#ts_entry.notes}]}.
 
 encode_datetime({{Year, Month, Day}, {Hour, Minute, Second}}) ->
-    lists:flatten(io_lib:format("~4.10.0B-~2.10.0B-~2.10.0BT~2.10.0B:~2.10.0B:~2.10.0B~3.10.0BZ", 
+    lists:flatten(io_lib:format("~4.10.0B-~2.10.0B-~2.10.0BT~2.10.0B:~2.10.0B:~2.10.0B.~3.10.0BZ", 
         [Year, Month, Day, Hour, Minute, Second, 000])).
 
 ejson_to_record(_Empty=#ts_timeline{}, EJSON) ->