[prometheus]: Add path metric per host

[erbesharat]

What this PR does / why we need it:
Adds path metric per host

Which issue this PR fixes:
fixes #174

[erbesharat]

Tests failed once but passed after I restarted the job.
Cause of failure:

go: golang.org/x/[email protected]: git -c protocol.version=0 fetch --unshallow -f https://go.googlesource.com/net refs/heads/*:refs/heads/* refs/tags/*:refs/tags/* in /go/pkg/mod/cache/vcs/4a22365141bc4eea5d5ac4a1395e653f2669485db75ef119e7bbec8e19b12a21: exit status 128:
  error: Could not read ab5485076ff3407ad2d02db054635913f017b0ed
  fatal: Failed to traverse parents of commit 44b7c21cbf19450f38b337eb6b6fe4f6496fb5b3
  error: remote did not send all necessary objects
go: error loading module requirements

Not sure but this might help or at least give us some info: golang/go#26594

[stp-ip]

Looks good. Will merge and we can see, how that makes our metrics more complex and more resource intensive.
Sidenote: Always happy for you to also join discussions on the issues before implementing one of the solutions. Discussion is great to get to know different viewpoints that I and others might have missed.