Allow the scans of multiple file paths and not only a single directory

[pombredanne]

Reported on chat:

@nicobucher wrote on Feb 20 21:52:
Hi aboutcode. I got a question regarding the scancode scanner: "Is it possible to provide a list of files (say e.g. a list of changed files of a pull request) to the scanner instead of a folder? So that the scanner only scans those files?"

[pombredanne]

And @pombredanne wrote on Feb 21 15:30:

@nicobucher welcome!
@nicobucher not for now. there might be a pending ticket
there is way to ignore file but not a way to pass more than one file as arguments
@nicobucher that said, what would you expect as an output in these cases? one JSON or several JSON? and would all the files in question share a common root directory or not?
@nicobucher If we think PR, then they would be under the same root, right?
adding this when there a common root may not be too complicated as it would not break the codebase/fs tree model used internally

[alexwahl]

Hi! I got the same usecase, I would like to provide a list of files to be scanned. I would expect one output file containing information about all files in the list. It would be nice if the files must not have the same root folder but this is no must have for me.