Enhance reset and the opcode dispatch strategy

[steveschnepp]

This is to cleanup the function table versus switch for opcode dispatch.

There is no need for unused functions to be compiled.

It also contains some RESET enhancements. As soft reset, hard reset and power-cycle isn't the same. So we can emulate powered down IDLE scenarios.

[steveschnepp]

Also, I'm wondering if you would mind moving to autoconf/automake.

I know that it has bad press, but I really like it. And it is ubiquitous. Much more than any modern alternative.