update dev deps

+all tests pass.

Note: the build removes `-webkit-box-shadow: none !important;` from the compiled CSS. I don't think that should have been there before. The webkit prefixed version hasn't been needed for a looooooong time. https://caniuse.com/#feat=mdn-css_properties_box-shadow

dist/css/main.css

@@ -211,7 +211,6 @@ textarea {
     background: transparent !important;
     color: #000 !important;
     /* Black prints faster */
-    -webkit-box-shadow: none !important;
     box-shadow: none !important;
     text-shadow: none !important;
   }

package.json

@@ -1,17 +1,17 @@
 {
   "devDependencies": {
-    "@babel/core": "^7.5.5",
-    "@babel/preset-env": "^7.5.5",
-    "@babel/register": "^7.5.5",
+    "@babel/core": "^7.6.4",
+    "@babel/preset-env": "^7.6.3",
+    "@babel/register": "^7.6.2",
     "apache-server-configs": "^3.2.1",
     "archiver": "^3.1.1",
     "del": "^5.1.0",
-    "eslint": "^5.16.0",
+    "eslint": "^6.5.1",
     "eslint-config-recommended": "^4.0.0",
-    "eslint-plugin-mocha": "^5.3.0",
+    "eslint-plugin-mocha": "^6.2.0",
     "glob": "^7.1.4",
     "gulp": "^4.0.2",
-    "gulp-autoprefixer": "^7.0.0",
+    "gulp-autoprefixer": "^7.0.1",
     "gulp-eslint": "^6.0.0",
     "gulp-header": "^2.0.9",
     "gulp-load-plugins": "^2.0.1",
@@ -19,11 +19,11 @@
     "gulp-replace": "^1.0.0",
     "jquery": "3.4.1",
     "main.css": "2.0.0",
-    "mocha": "^5.2.0",
+    "mocha": "^6.2.1",
     "modernizr": "3.7.1",
     "normalize.css": "8.0.1",
-    "ssri": "^6.0.1",
-    "strip-json-comments": "^2.0.1"
+    "ssri": "^7.0.1",
+    "strip-json-comments": "^3.0.1"
   },
   "engines": {
     "node": ">=8",