Updated Assignments overview (markdown)

Assignments-overview.md

@@ -67,11 +67,11 @@ If not specified otherwise than its mandatory item! Mandatory items are bold, op
   - **cmd** - description of command which will be executed
     - **bin** - the binary itself
     - _args_ - list of arguments which will be sent into execution unit
-  - _stdin_ - file to which standard input will be redirected, used only in external tasks, can be omitted
-  - _stdout_ - file to which standard output will be redirected, used only in external tasks, can be omitted
-  - _stderr_ - file to which error output will be redirected, used only in external tasks, can be omitted
   - _sandbox_ - wrapper for external tasks which will run in sandbox, if defined task is automatically external
     - **name** - name of used sandbox
+    - _stdin_ - file to which standard input will be redirected, can be omitted
+    - _stdout_ - file to which standard output will be redirected, can be omitted
+    - _stderr_ - file to which error output will be redirected, can be omitted
     - **limits** - list of limits which can be passed to sandbox
       - **hw-group-id** - determines specific limits for specific machines
       - _time_ - time of execution in second