docs/develop: Mass directory restructure.

Now vaguely follows the tree structure of "src", with the exception of
directories that described subsystems spanning more than one "kit" or
"server" (e.g. "media", "midi", "bluetooth") -- these have been left as their
own top-level directory within docs/develop.

docs/develop/servers/input/input_server threads

@@ -0,0 +1,12 @@
+Input_server threads
+
+input_server(10-Normal Priority)
+_input_server_event_loop_(103-Custom Priority)
+ScreenSaver Looper(10-Normal Priority)
+DevicesLooper(10-Normal Priority)
+w>Team Monitor(120-Real Time Priority)
+PS/2 Mouse(104-Custom Priority)
+AT Keyboard(104-Custom Priority)
+
+Legend:
+w>  This signifies that the thread is spawned from a parent process. (most likely from the input_server)