fix timer view
merge with master
setup for timer styling
sprocket problem
merge with master
add rest attributes for exercise migrations
link timer to rest stored rest attribute of exercises
make some color functions

one function returns background rgb values for an element. others set up a color changer function
add working interval coloring function
working colorizer function linked to timer
basic views and specs for timer function
merge with master
fix input values on colorizer
add rest to strong params
Merge pull request #45 from krauzer/timer

Timer functionality and design