Added ability to disable backdrop close feature for modals.

modal.js

@@ -10,14 +10,22 @@ class Modal extends IgniteElement {
         return {
             dialogClasses: null,
             modal: null,
-            modalInstance: null
+            modalInstance: null,
+            backdropClose: true
         };
     }
 
     render() {
         return this.template.child(
-            new div().class("modal").ref(this.modal).child(
+            new div()
-                new div().class("modal-dialog").class(this.dialogClasses).child(
+                .class("modal")
+                .data("backdrop", this.backdropClose, (value) => !value ? "static" : null)
+                .ref(this.modal)
+                .child(
+                    new div()
+                        .class("modal-dialog")
+                        .class(this.dialogClasses)
+                        .child(
                             new div().class("modal-content").child(
                                 new slot(this)
                             )
@@ -27,7 +35,7 @@ class Modal extends IgniteElement {
     }
 
     ready() {
-        this.modalInstance = new bootstrap.Modal(this.modal);
+        this.modalInstance = new bootstrap.Modal(this.modal, { backdrop: this.backdropClose ? "true" : "static" });
     }
 
     show() {