* Pass Go context down to Renderers
This is useful for cancellation or tracing.
* Add tracing spans to app
Also log things like number of nodes in Map, total number of reports.
* Add filters for pseudo nodes.
- Don't filter the internet node as a pseudo node.
- Rename pseudo filter to unmanaged/uncontained.
- Review feedback
- Move the FilterFoo funcs into the tests
- Drop the 'nodes' from filter labels.
* Fix experimental
Squash of:
* We have to keep all the container hostnames until the end so we can
count how many we've filtered
* Adding tests for ContainerHostnameRenderer and PodServiceRenderer with
filters
* Because we filter on image name we need the image name before
filtering
* Alternative approach to passing decorators.
* Refactor out some of the decorator capture
* Don't memoise decorated calls to Render
* Fixing filtered counts on containers topology
Tricky, because we need the filters to be silent sometimes (when they're
in the middle), but not when they're at the top, so we take the "top"
filter's stats. However, this means we have to compose all
user-specified filters into a single Filter layer, so we can get all
stats.
There are no more Silent filters, as all filters are silent (unless they
are at the top).
Additionally, I clarified some of the filters as their usage/terminology
was inconsistent and confused. Now Filter(IsFoo, ...) *keeps* only nodes
where IsFoo is true.
