only first time input (start time) can be changed now. added function which will determin wheather or not given item is first
showMenu() function optimalization
items gradient changed to linear from radial
default item color changed to blue
startTime is now saved to local storage
ukládání start time inputu při jeho změně
added html5 input validation to start time input. onblur returns to previous correct value
added html5 validation on duration input