Add build and install scripts for local development

Author: maatthc

Diff for: package.json

@@ -12,6 +12,10 @@
     "type": "git",
     "url": "https://github.com/sdras/vue-vscode-snippets.git"
   },
+  "scripts": {
+    "build": "vsce package -o vue-vscode-snippets-$npm_package_version.vsix",
+    "install": "code --install-extension vue-vscode-snippets-$npm_package_version.vsix"
+  },
   "keywords": ["Vue", "Vue 2", "Vue Snippets"],
   "extensionDependencies": ["octref.vetur"],
   "categories": ["Snippets"],

Diff for: yarn.lock

@@ -0,0 +1,4 @@
+# THIS IS AN AUTOGENERATED FILE. DO NOT EDIT THIS FILE DIRECTLY.
+# yarn lockfile v1
+
+