Fix threat-feed, improve ui, add eco filter

[pvdz]

This fixes the threat feed and improves the CLI side of things a bit;

• Fixes the queries (right now it defaulted to fetching zero entries...)
• Added an ecoSystem filter to only fetch reports for maven or npm or whatever
• Updated the help to explain the different filter options and what they mean
• Added a description box for the interactive table view; it will show the details for the highlighted row as well as the "description" verdict which explains why a package was flagged.
• Fixed date "ago" strings
• Tried to fix some UI glitches with column positioning. Mostly hacked around the table not properly calculating column widths for some cases, leading to a wrangled table view. In its current form it works and stuff is aligned, at least. We'll revisit this later.

Sample: