let next & previous buttons be enabled for changing month in detailed event entry dialog
In detailed event entry dialog, next button for month is disabled for December, and Previous button is enabled for January.
Ie, If the user is on December 2016, to switch to January 2017, the user have to change the year to 2017, and month to January, which requires too many user interactions. It would be nice if the user be able to click next button when the month is December that would change the month to January and increment the year by one. The same for Previous button in January too.