Improve CI caching (#416)

* Adjust linux distro to ubuntu 14.04

* Cache lib directory for speedy builds

* Fix path linking for default extensions

* Update reset

* Reset to head

* Improve caching

* Still run yarn in CI

* Update yarn before install

* Increase cache timeout

* Install vscode from vstar

* Undo data-dir changes to CLI, add back clean, remove unused CI func

* Remove additional flags added

* Remove unused dependency

* Reset vscode install dir so patching always works

package.json

@@ -15,7 +15,9 @@
   "devDependencies": {
     "@types/fs-extra": "^5.0.4",
     "@types/node": "^10.12.18",
+    "@types/tar": "^4.0.0",
     "@types/trash": "^4.3.1",
+    "cache-loader": "^2.0.1",
     "cross-env": "^5.2.0",
     "crypto-browserify": "^3.12.0",
     "css-loader": "^2.1.0",
@@ -34,6 +36,8 @@
     "sass-loader": "^7.1.0",
     "string-replace-loader": "^2.1.1",
     "style-loader": "^0.23.1",
+    "tar": "^4.4.8",
+    "terser-webpack-plugin": "^1.2.3",
     "ts-loader": "^5.3.3",
     "ts-node": "^7.0.1",
     "tsconfig-paths": "^3.8.0",