Upgrade Node dependencies across semver-minor (#500)

The only exception being `node-sass` which requires a major version-bump
to support Node 10

Author: ashmaroli

package.json

@@ -37,48 +37,48 @@
   "license": "MIT",
   "dependencies": {
     "brace": "0.9.1",
-    "classnames": "2.2.5",
-    "highlight.js": "^9.10.0",
+    "classnames": "2.2.6",
+    "highlight.js": "^9.15.10",
     "isomorphic-fetch": "2.2.1",
-    "js-yaml": "3.6.1",
+    "js-yaml": "3.13.1",
     "lint-staged": "^4.3.0",
-    "lodash": "4.13.1",
-    "moment": "2.17.1",
-    "prop-types": "^15.6.0",
+    "lodash": "4.17.15",
+    "moment": "2.24.0",
+    "prop-types": "^15.7.2",
     "react": "15.4.1",
     "react-ace": "4.1.5",
     "react-document-title": "^2.0.3",
     "react-dom": "15.4.1",
     "react-dropzone": "3.10.0",
     "react-hotkeys": "^0.9.0",
     "react-modal": "^1.7.3",
-    "react-notification-system": "0.2.7",
+    "react-notification-system": "0.2.17",
     "react-redux": "5.0.1",
     "react-router": "3.0.0",
-    "react-router-redux": "4.0.7",
+    "react-router-redux": "4.0.8",
     "react-textarea-autosize": "^5.1.0",
     "react-widgets": "3.4.5",
     "redux": "3.6.0",
     "redux-logger": "2.6.1",
     "redux-thunk": "2.1.0",
     "simplemde": "1.11.2",
-    "sortablejs": "1.4.2",
-    "underscore": "1.8.3"
+    "sortablejs": "1.8.4",
+    "underscore": "1.9.1"
   },
   "devDependencies": {
-    "babel-cli": "6.24.1",
-    "babel-core": "6.25.0",
+    "babel-cli": "6.26.0",
+    "babel-core": "6.26.3",
     "babel-eslint": "7.2.3",
     "babel-jest": "20.0.3",
     "babel-loader": "7.1.1",
     "babel-plugin-transform-react-constant-elements": "6.23.0",
-    "babel-plugin-transform-react-remove-prop-types": "0.4.6",
+    "babel-plugin-transform-react-remove-prop-types": "0.4.24",
     "babel-polyfill": "6.23.0",
-    "babel-preset-env": "1.6.0",
+    "babel-preset-env": "1.7.0",
     "babel-preset-react": "6.24.1",
     "babel-preset-react-hmre": "1.1.1",
     "babel-preset-stage-1": "6.24.1",
-    "browser-sync": "2.18.5",
+    "browser-sync": "2.26.7",
     "chalk": "1.1.3",
     "cheerio": "0.20.0",
     "coveralls": "^2.13.1",
@@ -97,9 +97,9 @@
     "mkdirp": "^0.5.1",
     "mocha": "2.4.5",
     "nock": "^8.0.0",
-    "node-sass": "3.7.0",
+    "node-sass": "4.9.4",
     "npm-run-all": "3.1.2",
-    "prettier": "^1.7.4",
+    "prettier": "^1.18.2",
     "react-addons-test-utils": "15.4.1",
     "react-test-renderer": "15.4.1",
     "redux-immutable-state-invariant": "1.2.4",