Merge pull request #27 from ptesarik/master

Add and update bootloader and a fix for up_n_down
voltage_readings now has an explanation of what we /can/ do.
voltage_readings chat log is now properly formatted
voltage_readings file description readability improved
up_n_down - unused define removed and typo fix

I suspect MAX_MODE was used in the past to prevent the mode counter from
going over and allowing mode changes from any other mode, but currently
any number of clicks while not in MODE_OFF (or locked and new mode is
MODE_LOCK) will turn the light off anyway.  Re-introduce if mode changes
while already in a mode are enabled?
Also fixed a typo.
saving a few bytes - variable and ternary ops.

Re-using the current_level variable for end_light_level determination
saved 4 bytes.  Changing the if-then-else to ternary operators saved 6
more.  Whitespace for readability.
Merge pull request #28 from EagleWorks/master

Saving a few bytes, minor clean-up
Merge pull request #31 from ptesarik/bootloader

Bootloader significantly reworked
Merge branch 'master' into bootloader