This new approach (CLOCK_CONF_ACCURATE=0) was not as inaccurate
as originally thought. In fact, it has pretty much the same
accuracy as the old, stack-hungry version.
* Renamed the define from CLOCK_CONF_ACCURATE (1: old) to
CLOCK_CONF_STACK_FRIENDLY (1: new) to stop implying
that one is more accurate than the other.
* Using CLOCK_CONF_STACK_FRIENDLY by default.
* Bit-Addressable SFRs are now accessed as such,
instead of (N)OR-ing the byte
* A routine was declared as CCIF but not defined as such. Fixed
* Deleted a leftover duplicate define
* Formatting
* Comment updates and clarifications
