Renamed and used constants

Some of these names were too vague, some did not reflect what they were
for, some were bare numbers that had no constants - cleaned them up.
Update README.md
Update README.md
Use same features array as 22HD, which works
Merge branch 'develop' of github.com:aidyw/bosto-2g-linux-kernel-module into develop
Improve formatting using kernel standards

Sorry for these inconsequential commits, just cleaning up for the
inevitable attempts to merge this driver back into the kernel tree.
Getting rid of the warnings

Removed the .ko file because build results should never be in Git.
Added conditions to select tool button presses when either pen or eraser whilst floating or in contact.