vswhere needs to be updated

[heaths]

I see you are using vswhere 1.0.62 which contains a possible deadlock issue from the CRT I fixed for version 2.1.3. I recommend you update to the latest to make sure this and any other changes are fixed. This also includes a fix to correctly output UTF-8 for JSON despite the console encoding, which will work better for localized installs.

A customer reported an issue where vswhere appears to be deadlocking. They may be using an older version since I see -version [15.0,16.0) which you fixed, but the version of vswhere can still deadlock.

[heaths]

Unfortunately, I can't fix this myself. Once I forked and started digging in, I see you're pulling it from a container. Instead, you might consider just pulling from https://www.nuget.org/api/v2/package/vswhere which will download the latest .nupkg, which is just a ZIP file. You can find vswhere.exe in tools/ at the root of the zip.

If you don't like the idea of pulling from a dynamic version (though I do maintain backward compatibility), you should at least update to the latest version.

[heaths]

I modified externals.sh to actually pull from nuget and used a fixed URL, though it wouldn't have to be. Modifications are to use getopts_long-like functionality (though, simple bash script to avoid dependencies) which don't rely solely on positional parameters (other than source and target) and make the rest of the "flags" more obvious. PR forthcoming.