Expand on the description of the two available patchsets (Closes #146)

docs/CONFIG.md

@@ -1,5 +1,5 @@
-Configuring which patches are used
-----------------------------------
+Description of the patch sets
+-----------------------------
 
 This repository has two sets of patches - one set for the keyboard
 changes and one for turning off the battery validation.  The battery
@@ -8,6 +8,28 @@ patches are disabled by default, but are easy to enable.
 Any combination of the two sets of patches can be enabled or disabled
 (even including a version with no patches at all - to revert all changes)
 
+### KEYBOARD patchset
+
+Applying this set of patches will adjust your Embedded Controller to support
+the slightly different keymapping used with a xx20 keyboard.  If you prefer
+to use the older 7-row keyboard instead of the newer xx30 6-row keyboard, then
+you want this patchset enabled.  It is enabled by default.
+
+### BATTERY patchset
+
+Applying this set of patches will disable the check that the system makes for
+Lenovo original batteries.  If you wish to use aftermarket batteries, then
+you want to enable this patchset.  It is disabled by default.
+
+Note that this authentic battery check was done by Lenovo for a good reason
+as aftermarket battery construction and quality is highly variable.  There
+have been a number of people who have discovered that their aftermarket
+battery is not working even after installing this patch and (so far) they
+have all found that the battery itself was broken.
+
+Configuring which patches are used
+----------------------------------
+
 There are several makefile targets that exist to help you configure which
 patches are enabled.  Choose one or more of the following commands to
 configure as you want: