Fixed #73 UI (sample color)
Fixed #73 UI (sample color)

sample color change
when the user change the value of color input
not only when input lost focus

Asqatasun/Contrast-Finder,dzc34/Contrast-Finder,Asqatasun/Contrast-Finder,Asqatasun/Contrast-Finder,dzc34/Contrast-Finder,dzc34/Contrast-Finder,Asqatasun/Contrast-Finder,dzc34/Contrast-Finder