Copy only changed assets

[matte00]

Hi @euclid1990 and thank you for you useful plugin.

Think you that will be possible copy to ouput directory only the changed files and not always all files?
I upload files to a remote server so send all files every times is not the best solution. What do you think about it?

[euclid1990]

@matte00 thank you for your suggestion, I will consider and find the solution to solve this problem.
If you have time, you can send the PR for this.