Converted Gulp 3.9 → 4.0, removed livereload, and fixed security issues

All done in one go, because things wouldn't build otherwise.

package.json

@@ -13,14 +13,13 @@
 		"babel-core": "7.0.0-bridge.0",
 		"babelify": "10.0.0",
 		"browserify": "16.2.3",
-		"gulp": "^3.9.1",
+		"gulp": "^4.0",
 		"gulp-autoprefixer": "^6.0.0",
 		"gulp-cached": "^1.1.1",
 		"gulp-chmod": "^2.0.0",
 		"gulp-concat": "^2.6.1",
 		"gulp-if": "^2.0.2",
 		"gulp-git": "^2.8.0",
-		"gulp-livereload": "^4.0.0",
 		"gulp-plumber": "^1.2.0",
 		"gulp-pug": "^4.0.1",
 		"gulp-rename": "^1.4.0",
@@ -32,15 +31,10 @@
 		"vinyl-source-stream": "2.0.0"
 	},
 	"dependencies": {
-		"bootstrap": "^4.1.3",
-		"jquery": "^3.3.1",
+		"bootstrap": "^4.3.1",
+		"event-stream": "^4.0.1",
+		"jquery": "^3.4.1",
 		"natives": "^1.1.6",
 		"popper.js": "^1.14.4"
-	},
-	"__COMMENTS__": [
-		"natives@1.1.6 for Gulp 3.x on Node 10.x: https://github.com/gulpjs/gulp/issues/2162#issuecomment-385197164"
-	],
-	"resolutions": {
-		"natives": "1.1.6"
 	}
 }