Fullcalendar: v4.0.0-beta.2 Release

BIG changes since last alpha release: (see https://fullcalendar.io/docs/v4/release-notes for more info) - all functionality is broken up into plugins - changed the names of many views (ex: agendaWeek -> timeGridWeek) - changed the names of the npm packages (ex: @fullcalendar/core) - technique for initializing a calendar (and using plugins) has changed - SuperAgent is no longer needed - Bootstrap 3 theme support dropped - jQuery UI theme support dropped - Bower support dropped - Composer support temporarily dropped - a new npm-run based dev workflow - bundled via Rollup (instead of Webpack)

Smaller changes since last alpha release: - no need to specify timeZoneImpl setting. simply use luxon or moment-timezone plugin instead - agendaEventMinHeight renamed to timeGridEventMinHeight - for registering a custom view use createPlugin instead of defineView - groupByDatesAndResources and groupByResources removed. Use datesAboveResources instead - removed the deprecated theme settings. use themeSystem instead - for Boostrap 4 theme support, specify themeSystem: 'boostrap' instead of ('bootstrap4')

Really obscure changes: - MAX_TIMELINE_SLOTS moved to (packageRoot).config.MAX_TIMELINE_SLOTS - touchMouseIgnoreWait moved to (packageRoot).config.touchMouseIgnoreWait - dataAttrPrefix moved to (packageRoot).config.dataAttrPrefix