Add support for a custom path in CollectorParams

[emiliauskas-fuzzy]

Library version:
0.6.0
Expected behavior:
able to set custom path for target collector
Actual behavior:
right now its not possible because of port append (443 or 80 or custom) which messes up actual path
Steps to reproduce:

just try to set
AsyncEmitter.createAndStart("collector.host.com/somepath", port = None, https = true)
and tracker will transform it to https://collector.host.com/somepath:443 instead of https://collector.host.com:443/somepath

I think easiest would be to update CollectorParams with extra field path: Option[String] which would be append to the uri.

[BenFradet]

Good idea 👍

[emiliauskas-fuzzy]

@BenFradet thanks, I think it can be easily added together with this URI PR done by @chuwy just by allowing path set here: 283ca5d#diff-07448d20291b73583919ed006d083f3bR156