Concise scripts

[bennypowers]

Allow users to define scripts like so:

"wireit": {
  "patch": "patch-package",
  "husky": "npx husky install",
  "postinstall": {
    "dependencies": [
      "patch",
      "husky"
    ]
  }
}

equivalent to

"wireit": {
  "patch": {
    "command": "patch-package"
  },
  "husky": {
    "command": "npx husky install"
  },
  "postinstall": {
    "dependencies": [
      "patch",
      "husky"
    ]
  }
}

[aomarks]

In these cases the one-liners could just be regular npm scripts, since there is nothing added by wireit to their behavior. (Note that wireit scripts can reference regular npm scripts as dependencies).

[bennypowers]

with wireit-only scripts (#653) landed, this could be useful to provide simple scripts without creating an 'entrypoint'