Added microtime for more unique ness - #180

How is it possible, for a file, to have micro_time attribute?

I think you can make use of this:
https://developer.mozilla.org/en-US/docs/Web/API/File/lastModifiedDate

What you have linked is deprecated and there is also chances of same name,same size and same lastModifiedTime,So im attaching a new one. File doesn't have any micro_time key, but im attaching one if there is no one.

relativePath += "-" + (lastModified || Date.now());
Sounds reasonable isn't?

@AidasK : What do you think?

Why do we need that generateUniqueIdentifier would modify our file instance?

Also more uniqueness means file might not get resumed, if this is the intention, I think it can be solved differently.

Also, there is a new property which is not deprecated https://developer.mozilla.org/en-US/docs/Web/API/File/lastModified

Using lastModified is what I suggested to add more uniqueness.
(Note that if lastModified changed, we may actually prefer not to resume such a file)
Does it mean you're rather favorable to a PR going into that direction? (I could soon provide one)

Yes, let’s use lastModified for more uniqueness