Collapse Lists.

Thanks to xet7 !

models/swimlanes.js

@@ -107,6 +107,13 @@ Swimlanes.attachSchema(
       type: String,
       defaultValue: 'swimlane',
     },
+    collapsed: {
+      /**
+       * is the swimlane collapsed
+       */
+      type: Boolean,
+      defaultValue: false,
+    },
   }),
 );
 
@@ -232,6 +239,10 @@ Swimlanes.helpers({
     return ret;
   },
 
+  isCollapsed() {
+    return this.collapsed === true;
+  },
+
   board() {
     return ReactiveCache.getBoard(this.boardId);
   },
@@ -274,6 +285,10 @@ Swimlanes.mutations({
     return { $set: { title } };
   },
 
+  collapse(enable = true) {
+    return { $set: { collapsed: !!enable } };
+  },
+
   archive() {
     if (this.isTemplateSwimlane()) {
       this.myLists().forEach(list => {