Change focus on arrow up/down and change column on Tab

[vishalkr07]

The current implementation is to change the focus when Tab is entered, but it would be a better experience if the user can change the focus by using the arrow up/down key and change the columns (from hh to mm) using the tab key. Now if the user wants to select the minute after selecting the hour value, he/she has to tab over all the remaining hour values.