Refactor stream tracking

[cboulay]

Based off another PR so only pay attention to https://github.com/labstreaminglayer/App-LabRecorder/commit/4a018cd50110603910dd5f0cd19bbe61ef8bb7a4

• Added autoStart to config (Fixes #21)
  • But this didn't make sense unless RequiredStreams was working, which it wasn't.
• resolved streams are now kept track of in knownStreams
  • QList, not QSet, means we can have name-host duplicates (Fixes #31)
  • But it's a struct that also holds the source id so duplicates are unlikely.
• missing & required streams are kept track of in missingStreams
  • Here we only have "name (host)"
  • The idea of "RequiredStream" is now a stream that will be checked at program launch. Any stream that's checked will stay in the list even if unresolved. If the user checks a resolved stream, then that stream goes offline, and the user clicks update, that stream is now a requires/missing stream. Similarly, if the user unchecks a stream that was originally "required", then updates and it's not resolved, the previously-required stream would disappear from the list.
• "name (host)" now converted to xpath query so streams can be resolved after the file has started. Fixes #29
  • FYI (host) cannot have any spaces within the parentheses.

[cboulay]

Here's a Win64 build for anyone willing to test it out. Thanks!

LabRecorder_1.14b1_Win64.zip

You can also grab the artifacts from the top right corner of the CI report: https://github.com/labstreaminglayer/App-LabRecorder/pull/38/checks?check_run_id=974619861

[cboulay]

Changed base to fix_cfg_parsing, which is the branch used in PR #37, to isolate discussion in this PR.