Scan binaries located on the path

[bhamail]

Trying to capture some of @DarthHater 's ideas for future Ahab enhancements.

It is great that Ahab scans OS packages (.rpm, .deb, .apk, etc), but there are also many cases where someone will curl or wget some binary file down and install it directly into the /usr/bin folder (or somewhere on the PATH).

To detect these, Ahab could:

1. enumerate all the directories on the OS PATH.
2. in each directory, look for binaries and try to determine if the binary has a hashcode of a file known to be from an .rpm/.deb. Could also try to detect vulns for binaries that do not appear to be from a .rpm/.deb.

cc @bhamail / @DarthHater / @ken-duck / @ButterB0wl