Add information about Script ID(libraryId) in README.md

[daikikatsuragawa]

The GAS editor has evolved.

Script ID(libraryId) is required to use the library.
We would be happy to write that information in README.md.

I didn't know Script ID, so I temporarily used the old editor.

[daikikatsuragawa]

I'm sorry in Japanese.
Script ID(libraryId) is required like this in new edditor.

[mkataoka73]

I had the same problem, and I found that we can see it on ./clasp.json page.

Sorry for the inconvenience, but I'm not sure if it's okay to paste the image here, so I only put the URL.

[daikikatsuragawa]

@jlmercury

Oh, thank you! I knew for the first time that it was the same.
It may not be necessary, but I think that it is kind to users who have not confirmed GitHub firmly, so I think that it is better to include it.

@munierujp
The final decision is left to the project owner.