refactor for arduino 1.5x
cleanup; build time option to disable button; readme
update readme
stepsPerNotch is now runtime configurable
change order of constructor arguments, makes more sens this was
Merge branch 'master' of github.com:0xPIT/encoder into arduino

Conflicts:
	README.md
fix conflict with readme
add hints to examples
check button only when a pin has been provided
Merge pull request #1 from 0xPIT/arduino

Arduino version