Update library with security vulnerabilities (#65)

diff --git a/package-lock.json b/package-lock.json
index 7387213..a04d0eb 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -2950,9 +2950,9 @@
       }
     },
     "handlebars": {
-      "version": "4.1.2",
-      "resolved": "https://registry.npmjs.org/handlebars/-/handlebars-4.1.2.tgz",
-      "integrity": "sha512-nvfrjqvt9xQ8Z/w0ijewdD/vvWDTOweBUm96NTr66Wfvo1mJenBLwcYmPs3TIBP5ruzYGD7Hx/DaM9RmhroGPw==",
+      "version": "4.7.2",
+      "resolved": "https://registry.npmjs.org/handlebars/-/handlebars-4.7.2.tgz",
+      "integrity": "sha512-4PwqDL2laXtTWZghzzCtunQUTLbo31pcCJrd/B/9JP8XbhVzpS5ZXuKqlOzsd1rtcaLo4KqAn8nl8mkknS4MHw==",
       "dev": true,
       "requires": {
         "neo-async": "^2.6.0",
@@ -6565,14 +6565,23 @@
       "dev": true
     },
     "uglify-js": {
-      "version": "3.6.0",
-      "resolved": "https://registry.npmjs.org/uglify-js/-/uglify-js-3.6.0.tgz",
-      "integrity": "sha512-W+jrUHJr3DXKhrsS7NUVxn3zqMOFn0hL/Ei6v0anCIMoKC93TjcflTagwIHLW7SfMFfiQuktQyFVCFHGUE0+yg==",
+      "version": "3.7.6",
+      "resolved": "https://registry.npmjs.org/uglify-js/-/uglify-js-3.7.6.tgz",
+      "integrity": "sha512-yYqjArOYSxvqeeiYH2VGjZOqq6SVmhxzaPjJC1W2F9e+bqvFL9QXQ2osQuKUFjM2hGjKG2YclQnRKWQSt/nOTQ==",
       "dev": true,
       "optional": true,
       "requires": {
-        "commander": "~2.20.0",
+        "commander": "~2.20.3",
         "source-map": "~0.6.1"
+      },
+      "dependencies": {
+        "commander": {
+          "version": "2.20.3",
+          "resolved": "https://registry.npmjs.org/commander/-/commander-2.20.3.tgz",
+          "integrity": "sha512-GpVkmM8vF2vQUkj2LvZmD35JxeJOLCwJ9cUkugyk2nuhbv3+mJvpLYYt+0+USMxE+oj+ey/lJEnhZw75x/OMcQ==",
+          "dev": true,
+          "optional": true
+        }
       }
     },
     "underscore.string": {