feat: upgrade angular draggable droppable package

BREAKING CHANGE: The UMD entry point for the `angular-draggable-droppable` package has changed from `angular-draggable-droppable/dist/umd/angular-draggable-droppable.js` to `angular-draggable-droppable/bundles/angular-draggable-droppable.umd.js`. System.js users will need to update their config accordingly.

Also the dragStart output was renamed to dragPointerDown. Users using a custom template for the root day or week view components will need to adjust their templates accordingly.

package.json

@@ -162,7 +162,7 @@
     "@angular/core": ">=5.0.0 <7.0.0"
   },
   "dependencies": {
-    "angular-draggable-droppable": "^1.1.1",
+    "angular-draggable-droppable": "^2.0.0",
     "angular-resizable-element": "^2.0.0",
     "calendar-utils": "0.0.59",
     "date-fns": "^1.28.5",

src/modules/day/calendar-day-view.component.ts

@@ -84,7 +84,7 @@ export interface DayViewEventResize {
             [dragAxis]="{x: false, y: dayEvent.event.draggable && currentResizes.size === 0}"
             [dragSnapGrid]="{y: eventSnapSize}"
             [validateDrag]="validateDrag"
-            (dragStart)="dragStart(event, dayViewContainer)"
+            (dragPointerDown)="dragStart(event, dayViewContainer)"
             (dragEnd)="eventDragged(dayEvent, $event.y)"
             [style.marginTop.px]="dayEvent.top"
             [style.height.px]="dayEvent.height"

src/modules/week/calendar-week-view.component.ts

@@ -76,7 +76,7 @@ export interface WeekViewEventResize {
           [dragAxis]="{x: weekEvent.event.draggable && currentResizes.size === 0, y: false}"
           [dragSnapGrid]="{x: dayColumnWidth}"
           [validateDrag]="validateDrag"
-          (dragStart)="dragStart(weekViewContainer, event)"
+          (dragPointerDown)="dragStart(weekViewContainer, event)"
           (dragEnd)="eventDragged(weekEvent, $event.x, dayColumnWidth)">
           <mwl-calendar-week-view-event
             [weekEvent]="weekEvent"