Add unpack as a processor

[Dotan J. Nahum]

Suggestion / Feature Request

Add support for unpacking files as a preprocessor so that next matchers can match against uncompressed content.

• use https://github.com/rusty-ferris-club/decompress for unpacking
• first, walking the filesystem happens, so unpacking should happen somewhere here: https://github.com/rusty-ferris-club/recon/blob/master/recon/src/workflow.rs#L152

important

• see that unpacking happens and then matching can happen later
• no need for recursive unpacking
• handle errors gracefully -- continue running when there are files that cannot be unpacked