Merge branch 'collection-fixes-and-KnownVuln' into 'master'

add KnownVuln anti-feature, and other fixes

This is a bit of a random collection of things that I have added in the process of working on the drozer/scanner support, YAML support, etc.  The only new things are:

* adding new AntiFeature for security issues: `KnownVuln`
* removing broken, incomplete XML metadata support

Everything else included are just code improvements.  This also includes the first check for `KnownVuln`, which is a scanner to check whether custom OpenSSL binaries in apps are not old with known vulnerabilities.  `KnownVuln` will then ultimately be used for things like the drozer scanner !187

See merge request !189