formatted JS and CSS and added ability for dev to specify which arrows go up or down and a function to format the output

formatted JS and CSS and added ability for dev to specify which arrows go up or down and a function to format the output
added options: custom_classes (string) and start_time (array, ex: [5, 0, 'AM'] would set the initial time to 5:00 AM)
remember what the selected value was so it doesn't reset when the user opens the picker again
made the time picker keyboard friendly, using inputs for the values (should make arrow keys work too, but didn't do that yet)
Merge pull request #1 from akinnee/master

formatted JS and CSS and added ability for dev to specify which arrows g...