Run a Scale Command on multiple files

[alexkornitzer]

For Scales such as Yara it would be super useful to run a rule on many files and see if there were any hits. For this the API and the Scale commands functionality will have to be extended. A new form of command prototype will be required, one that takes a list of hashes instead of a FileStorage object. This still needs to be thought out and scoped, but will probably roughly be how it is implemented.

Note: This cannot be implemented until #4 is implemented