We capture the ParseStarted event in toaster_ui.log as the start point for a build initiated by Toaster ("Build" button etc.). We can then create a per-build log for just that build, which includes all of the pertinent information, including the "Build configuration" section output by bitbake.

However, we can't use the ParseStarted event for builds initiated outside Toaster, as we don't capture it. This may be because that event is never fired for cli builds (from Toaster's point of view), or because we miss it, or because bitbake only fires it for the type of builds we trigger from Toaster itself. (Needs investigation.) We have to fall back on BuildStarted instead.

Consequently, we don't capture the "Build configuration" in the Toaster logs for cli builds.

See bitbake/lib/bb/ui/toasterui.py for the place where we do event capture.

To reproduce:

1. Start toaster in build mode.
2. Trigger a build from toaster (e.g. zlib). 
3. Once complete, go to the build dashboard and download the build log. It shows the build configuration.
4. Stop toaster, and start it in analysis mode.
6. Run a build from the command line.
7. Download the build log, and note that the build configuration is missing. This is because the ParseStarted event wasn't captured, and we had to fall back on BuildStarted.

We need to get toaster to a state where the build log for command-line builds is equivalent to the build log for toaster-initiated builds, i.e. includes the build configuration. This should be possible if can get ParseStarted events for cli builds.