Update README with controller pairing details (#32)

* Update README with controller pairing details

Clarified the pairing process for the controller and added details about charging limitations and the pogo pins method.

* Add basic testing guide

README.md

@@ -21,7 +21,7 @@ There are two fundamental problems with the controller:
 
 [![OpenPuck Intro](https://img.youtube.com/vi/gSaqO9oqq9s/0.jpg)](https://www.youtube.com/watch?v=gSaqO9oqq9s)
 
-OpenPuck uses a [Pro Micro NRF52840](https://www.amazon.com/dp/B0GSZ7FD6T) ($8 on Amazon, possibly cheaper elsewhere) which uses a radio similar to the one being used by the controller and the puck. Once the arduino sketch is uploaded it emulates the puck over USB to Steam by default and allows pairing the controller normally (almost, the lizard mode for when Steam is off might not be 1:1).
+OpenPuck uses a [Pro Micro NRF52840](https://www.amazon.com/dp/B0GSZ7FD6T) ($8 on Amazon, possibly cheaper elsewhere) which uses a radio similar to the one being used by the controller and the puck. Once the arduino sketch is uploaded it emulates the puck over USB to Steam by default and allows pairing the controller by having both the copycat and the controller being plugged into USB together on the same computer. Note that the lizard mode for when Steam is off might not be 1:1. Obviously it can't charge the controller and cannot pair using the pogo pins method used by the official puck.
 
 At any point you can hold all 4 back buttons and press X to switch over to ***Xbox mode** which maps all canonical inputs to their expected counterparts (plus L4 -> LB, L5 -> L3, etc which are configurable). In this mode the right trackpad acts as a mouse but at present this only works in Android and SteamOS.
 

docs/TESTING_GUIDE.md

@@ -0,0 +1,13 @@
+## What to test before merging a change
+
+- Can you pair a controller?
+- Does the controller connect?
+- Does the controlelr work normally in Steam Controller mode, do the haptics work, is the gyro working?
+- Can you shut the controller off using Steam + Y?
+- Does the controller reconnect?
+- Can you change modes via the chords?
+- Can you change modes via webusb?
+- Do the modes work as expected (including gyro in gyro modes)
+- Is signal quality shown?
+- Is battery level shown and correct?
+- Is the polling rate and response rate the same? Is it around 250hz?