message: Tree: cleanup launch.json
  mocha now gets most of the needed config from its config file, so most
  of the arguments can be removed.
  Also the launch target name has been changed.
diff: "version": "0.2.0",
  "configurations": [
  {
  - "name": "Merge Tree Test",
  + "name": "Tree Tests",
  "type": "node",
  "request": "launch",
  "program": "${workspaceRoot}/../../../node_modules/mocha/bin/_mocha",
  - "args": ["dist/test", " --recursive", "--no-timeouts", "--exit"],
  + "args": ["--no-timeouts"],
  "cwd": "${workspaceRoot}"
  }
  ]
  