Fixed timeline creation, API logical fixes.

* Resolved issues:

    * #0006: Fix timeline menu UI.
    * #0015: Create new timeline button in timeline menu.
    * #0017: Implement timeline creation.

* Removed ts_api:post_timeline/3, corresponded to `POST` to
  `/ts_api/timelines/<user-id>`, which makes no sense as there is no way to
  auto-generate new timeline-ids.
* Changed ts_api:put_timeline/3 to use ts_timeline:write. This resolved #0017.
* Changed ts_api:put_entry/4 to use ts_entry:write.
* Implemented ts_entry:write/1 and ts_timeline:write/1. These functions are
  simple passthroughs to mnesia:dirty_write/1.
* Added clarifing documentation for ts_json:record_to_ejson JSON formats.
* Renamed ts_json:ejson_to_record/2 to ts_json:ejson_to_record_strict/2 and
  added ts_json:ejson_to_record/2 as a lax version of the same.
* Updated all ts_api functions to use updated ts_json methods.

src/ts_json.erl

@@ -1,10 +1,17 @@
 -module(ts_json).
--export([encode_record/1, record_to_ejson/1, ejson_to_record/2]).
+-export([encode_record/1, record_to_ejson/1, ejson_to_record/2, ejson_to_record_strict/2]).
 
 -include("ts_db_records.hrl").
 
 encode_record(Record) -> lists:flatten(json:encode(record_to_ejson(Record))).
 
+% User JSON record structure:
+% {"id":        "john_doe",
+%  "name":      "John Doe",
+%  "email":     "john.doe@example.com",
+%  "join_date": "2011-01-01T12:00.000Z",
+%  "ext_data":  {"last_timeline", "personal"}}
+
 record_to_ejson(Record=#ts_user{}) ->
     {struct, [
         {id, Record#ts_user.username},
@@ -13,6 +20,12 @@ record_to_ejson(Record=#ts_user{}) ->
         {join_date, encode_datetime(Record#ts_user.join_date)},
         {ext_data, Record#ts_user.ext_data}]};
 
+% Timeline JSON record stucture:
+% {"user_id":   "john_doe",
+%  "id":        "personal",
+%  "created":   "2011-01-01T14:00.000Z",
+%  "description:"Personal time-tracking."}
+
 record_to_ejson(Record=#ts_timeline{}) ->
     % pull out the username and timeline id
     {Username, TimelineId} = Record#ts_timeline.ref,
@@ -24,6 +37,14 @@ record_to_ejson(Record=#ts_timeline{}) ->
         {created, encode_datetime(Record#ts_timeline.created)},
         {description, Record#ts_timeline.desc}]};
 
+% Entry JSON record structure:
+% {"user_id":       "john_doe",
+%  "timeline_id":   "personal",
+%  "id":            "1",
+%   "timestamp":    "2011-01-01T14:01.000Z",
+%   "mark":         "Workout.",
+%   "notes":        "First workout after a long break."}
+
 record_to_ejson(Record=#ts_entry{}) ->
     % pull out the username, timeline id, and entry id
     {Username, TimelineId, EntryId} = Record#ts_entry.ref,
@@ -44,19 +65,58 @@ 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", 
         [Year, Month, Day, Hour, Minute, Second, 000])).
 
-ejson_to_record(_Empty=#ts_timeline{}, EJSON) ->
+ejson_to_record(Rec=#ts_timeline{}, EJSON) ->
     {struct, Fields} = EJSON,
 
-    #ts_timeline{
-        ref = {undefined, undefined},
+    Created = case lists:keyfind(created, 1, Fields) of
+        false -> undefined;
+        {created, CreatedVal} -> decode_datetime(CreatedVal)
+    end,
+
+    Desc = case lists:keyfind(description, 1, Fields) of
+        false -> undefined;
+        {description, DescVal} -> DescVal
+    end,
+
+    Rec#ts_timeline{
+        created = Created,
+        desc = Desc };
+
+ejson_to_record(Rec=#ts_entry{}, EJSON) ->
+    {struct, Fields} = EJSON,
+
+    Timestamp = case lists:keyfind(timestamp, 1, Fields) of
+        false -> undefined;
+        {timestamp, TSVal} -> calendar:datetime_to_gregorian_seconds(
+            decode_datetime(TSVal))
+    end,
+
+    Mark = case lists:keyfind(mark, 1, Fields) of
+        false -> undefined;
+        {mark, MarkVal} -> MarkVal
+    end,
+
+    Notes = case lists:keyfind(notes, 1, Fields) of
+        false -> undefined;
+        {notes, NotesVal} -> NotesVal
+    end,
+
+    Rec#ts_entry{
+        timestamp = Timestamp,
+        mark = Mark,
+        notes = Notes}.
+
+ejson_to_record_strict(Rec=#ts_timeline{}, EJSON) ->
+    {struct, Fields} = EJSON,
+
+    Rec#ts_timeline{
         created = decode_datetime(element(2, lists:keyfind(created, 1, Fields))),
         desc = element(2, lists:keyfind(description, 1, Fields))};
 
-ejson_to_record(_Empty=#ts_entry{}, EJSON) ->
+ejson_to_record_strict(Rec=#ts_entry{}, EJSON) ->
     {struct, Fields} = EJSON,
 
-    #ts_entry{
-        ref = {undefined, undefined, undefined},
+    Rec#ts_entry{
         timestamp = calendar:datetime_to_gregorian_seconds(decode_datetime(
             element(2, lists:keyfind(timestamp, 1, Fields)))),
         mark = element(2, lists:keyfind(mark, 1, Fields)),