Add task_list and task_history links.

Author: Pavel Kovalenko

README.md

@@ -7,6 +7,10 @@ The original engine is used in S.T.A.L.K.E.R. Call of Pripyat game released by G
 It is a place to share ideas on what to implement, gather people that want to work on the engine,
 and work on the source code.
 
+Current task list: [doc/design/task_list.txt](doc/design/task_list.txt)
+
+Task history: [doc/design/task_history.txt](doc/design/task_history.txt)
+
 Build instructions can be found [here](https://github.com/openxray/xray-16/blob/master/doc/howto/build.txt).
 
 If you find a bug or have an enhancement request, file an [Issue](https://github.com/openxray/xray-16/issues).