effect will execute depend on LED on/off
set target color if and only if variation option is selected
commit effect.py
move all effects to new file.
manage effect based on selection
handle effects dynamically
Fix interrupt
Minor refactor and bug fixes
Correct variation algorithm
Stop all timer when exit the program
Control variation effect via EffectController
Fixed BUG: when select both random and variate cuases their timer to start concurrently
increase speed of variation
Merge branch 'effect'