vsdownload: Add an option to skip packages that do not match host arch

[huangqinjin]

Depends on #140.

Some packages have their host arch in their ids, e.g.

"Microsoft.VisualCpp.Tools.HostARM64.TargetX64"
"Microsoft.VisualCpp.Tools.HostARM64.TargetX86"
"Microsoft.VisualCpp.Tools.HostX64.TargetX64"
"Microsoft.VisualCpp.Tools.HostX64.TargetX86"

I think it is pretty safe to skip packages if their ids do not match host arch.

PR #140

Selected 544 packages, for a total download size of 2.9 GB, install size of 8.9 GB

PR #148

Selected 475 packages, for a total download size of 2.7 GB, install size of 8.5 GB

[mstorsjo]

Thanks, this looks like a nice addition! However for some cases I guess it would be nice to be able to unpack all of them; would it be possible to add an option that lets the user get all of them?

[huangqinjin]

A option is reasonable to me. But the main reason for me is that such filters based on host arch will going to be wrong in future, e.g. I want to filter packages based on their chip, machineArch and productArch.

Is --only-host a good name? What is the default value we want?

[mstorsjo]

A option is reasonable to me. But the main reason for me is that such filters based on host arch will going to be wrong in future, e.g. I want to filter packages based on their chip, machineArch and productArch.

Is --only-host a good name? What is the default value we want?

This looks like a reasonable name, and yes, we want the default to be to only unpack things for the host arch - as normal users won't need to think about this option. Thanks!

[mstorsjo]

LGTM