DetailsLogSet on|off

[glenncarr]

Attached is a mod for the latest source (2.37+) to add a DetailsLogSet on|off command.

We needed this for a couple of reasons:
1. Our support folks needed to see the details of the install, and the output generated by LogSet included too much extra info, unrelated to the stuff they needed to see.
2. We wanted the same output for a silent install.

I ended up simply mimicking the behavior of LogSet, the only difference being that the resulting log file is $INSTDIR\install_details.log (instead of $INSTDIR\install.log as it is for LogSet). Since this was for our needs, I also didn't provide for conditional compilations as is currently done for LogSet -- the functionality is there all the time with these mods.

This doesn't handle *everything* sent to the details listview, it only handles output generated by DetailPrint and the nsExec::ExecToLog plug-in command, which does happen to handle all the output for our installs -- it just might not for yours.

This implementation certainly has room for improvement, but it works. One aspect that certainly gives me heartburn is a dependency on the nsExec plug-in source to the exehead source. Oh well.

I'm not necessarily suggesting this make it into the official release, I'm just throwing it out there in case anyone else might need this. I have also built an NSIS installer for these modified binaries if anyone would like to test it.