ps2: moved ps2 microsoft mouse example

- moved example of host-to-mouse configuration and mouse-to-host movement packets for
a 4-byte Microsft Mouse communicating with a Windows host into ps2/mouse directory
- Added README for the ps2/mouse directory, explaining the two examples

ps2/mouse/README

@@ -0,0 +1,36 @@
+--------------------------------
+PS/2 Mouse
+--------------------------------
+
+This is a collection of PS/2 mice communication examples.
+
+For details see:
+http://www-ug.eecg.utoronto.ca/desl/nios_devices_SoC/datasheets/PS2%20Protocol.htm
+http://www-ug.eecg.utoronto.ca/desl/nios_devices_SoC/datasheets/PS2%20Mouse%20Protocol.htm
+
+
+ps2_mouse_host_setup_and_movement.sr
+------------------------------
+
+This file contains a portion of setup from a QNX host to a trackball PS2 mouse.
+The mouse packets are 3 bytes long (standard mouse, no scrollwheel)
+The sample includes x movement, y movement, and a click.
+
+
+ps2_microsoft_mouse_initialize_and_move.sr
+------------------------------
+
+This file contains setup and communication between a Windows host and a microsoft mouse.
+The host releases the clock simultaneous to pulling the data low, which makes it challenging to 
+distinguish between "request-to-send" and a regular start-bit.
+
+Initialize a ps2 mouse, configure it; the mouse then reports movement data.
+
+- host resets device, waits for reset to complete
+- host sets sample rate to 200, 100, 80 - this activates reporting scroll wheel data is available
+- host sets device to maximum sample rate: 200; resolution=1: 2 count/mm; 1:1 scaling, stream mode
+- host gets device id, enable data reporting
+- after a delay, the mouse is moved, and reports it's changing location, in sequences of 4 bytes:
+    - flags, x movement, y movement, z (scroll wheel) movement.
+    - the sample data does not include any button presses or scroll wheel movement
+