better defaults for file.save

[calvinmetcalf]

file.save should probably default to {resumable: false}, as far as I know resumablility is not going to give any benefit to uploading files in single chunks but can have some performance penalties. In a test I wrote where I had to upload 100 small text files turning resumability off speed the test up from over a minute to a couple seconds.

[stephenplusplus]

Thanks for contributing!

@alexander-fenster wdyt? For historical reference:

• storage: support resumable uploads google-cloud-node#299
• Remove resumable option from file.createWritableStream google-cloud-node#399

[calvinmetcalf]

at the very least improving the documentation to make it clear that this setting is available and should be turned off.

[stephenplusplus]

We have a blurb about it in the method description here: https://cloud.google.com/nodejs/docs/reference/storage/1.4.x/File.html#createWriteStream

But the docs are very broken in that none of the options to a method are documented. We have an issue about that here: googleapis/google-cloud-node#2783

[stephenplusplus]

Ah, noticed you're using save. We could add the same note in the method description, or let the fix for googleapis/google-cloud-node#2783 show that resumable exists.