columnFormat *1.3* ================== Determines the text that will be displayed on the calendar's column headings.
String/[View Option Hash](../views/View_Option_Hash), *default*: { month: 'ddd', // Mon week: 'ddd M/d', // Mon 9/7 day: 'dddd M/d' // Monday 9/7 }
Uses [formatDate](../utilities/formatDate) formatting rules. A single string will set the title format for all views. A [View Option Hash](../views/View_Option_Hash) may be provided to target specific views (this is what the default does).
A View Option Hash can only be provided in version 1.4 and later.