Grype filtering through CVSS vector

**What would you like to be added**:

Grype currently ouputs a CVSS vector. Grype also has the ability to set a config file describing the kind of components that should be filtered from the output. It would be great if we can filter grype outputs based on certain parts of the CVSS vector (for eg. network exploitable vuln.)

**Why is this needed**:

Allows users to create filters for CVEs that actually affect their runtime env.

**Additional context**:

https://www.first.org/cvss/calculator/3.0

TODO: How to express the filter string/configuration.

Review Grype's existing configuration-based component filtering and how CVSS vectors are produced, then consult the linked CVSS 3.0 calculator context. The open design question is how a filter string or configuration should express selected CVSS attributes; done means users can configure those filters and Grype excludes matching vulnerabilities from its output.

Written by the indexing model from the issue text.