fix #714, Add process Architecture to the ps command

[timwr]

Hi all, I wanted to learn a bit of golang and familiarise myself with sliver, so I thought I'd have a go at fixing #714 since it seemed straightforward.
I've opened a draft PR because I have not fully tested this, and I have not implemented macOS, but I wanted to open this as a draft pr early to get feedback.

Details

This change uses IsWow64Process on Windows and reads the elf header from /proc/<pid>/exe on Linux to determine the architecture. macOS is not implement yet, but I suspect it can be achieved with sysctlnametomib("sysctl.proc_cputype",...

Verification

make pb
make linux
[server] sliver > generate --http example.com --os linux
[server] sliver (NAME_HERE) > ps
Output:

[server] sliver (NAME_HERE) > ps

 Pid    Ppid   Owner              Arch     Executable
====== ====== ================== ======== ===========================================================
 1      0      root               x86_64   /sbin/init
 2      0      root                        kthreadd

...

[moloch--]

Looking pretty good @timwr remove draft status when you think it's ready.

[rkervella]

We can leave macos support aside for now, I'll add it when I get some time. Not super urgent to have that feature for this OS anyway.

[moloch--]

Is there even a version of MacOS that supports 32-bit processes that we target?

[rkervella]

I have no idea, but it might matter with stuff like ARM native vs X86 via rosetta. And looks like sysctl.proc_cputype can give us the info, so I figure it shouldn't be too hard to list.

[moloch--]

Bypassing commit signing requirement.

[justinsteven]

@timwr thank you! 🙏 I only just saw this today when I got the ping that it closes the issue. I've logged #751 which is some weirdness on x86 installations of Windows