[Request for comment] DBus pcap visualizer tool recent updates

[Sui Chen]

Hello OpenBMC,

This is about some recent updates to the tool that could be thought of
as a visual version of Wireshark geared for OpenBMC; it is a desktop
app that runs on a host, opens a DBus PCAP file that can be obtained
by `busctl capture` on a BMC, and draws time lines. It draws a time line
graph, and draws some design ideas from other profiling tools.

The tool has been iterated for a few times and recent small
improvements include:
  - Prompts for the user to install dependencies
  - Ability to display overlapping DBus requests
  - Ability go group sensor PropertyChanged events together

Intended use cases:
  - Grab a PCAP on a normally-running BMC and understand what's happening on it.
  - Grab a PCAP on a BMC with problems and see if it's possible to
find a problem form the DBus point of view.

Some comments we're looking for include:
  - Is the UI intuitive?
  - Does it make understanding the operations of an OpenBMC-based
system a bit easier?
  - Does it address your problems when developing for OpenBMC? (It has
been helpful for us in a few circumstances)

The tool can be found here:
https://gerrit.openbmc-project.xyz/c/openbmc/openbmc-tools/+/34263

Thanks!