Expand EEPROM configuration options

[phillipjohnston]

Great request from Kelley:

Could some more parts of the bootloader be configured in the arduino EEPROM? e.g. timeout, etc. To lessen the frequency up needing to flash a new bootloader.

For the timeout:

I would probably disable it by default, and provide instructions for programming a boot-up connection delay if desired by the user.

[phillipjohnston]

Kelley's feedback on the option:

I like the opton. I think it's OK to delay by default. (to help people get going). The optional lower the delay interval. In addition to the docs, consider putting such hints in the debug output. So people see it right away without search docs

Will need to see how to better add debug strings...

[phillipjohnston]

Closed wrong issue in commit bcbb0a7