Fixed a problem with RGB fadeout.
Change the default color value to 0.
Change to the way the scheduler works. This was supposed to be a tweak
but it became an overhaul! 

What's done: 
 - Schedule is a vector of const char * instead of Show *, each entry is
a CLI command. 
 - Schedule takes commands:
    - stop/start: Start and stop the scheduler 
    - sleep <n>: Wait. This implements the timeouts
    - next: Breaks a sleep.
  - The Show class is useless now.
  
The main file was updated to use the new system (and do the same
patterns). Now there's a way to control sparkle and other parameters
from the presets.