Help: Add notes for topic 'console-pool'

Help/release/dev/console-pool.rst

@@ -0,0 +1,8 @@
+console-pool
+------------
+
+* The :command:`add_custom_command` and :command:`add_custom_target`
+  commands learned a new ``USES_TERMINAL`` option to request that
+  the command be given direct access to the terminal if possible.
+  The :generator:`Ninja` generator will places such commands in the
+  ``console`` pool.