Support CPU detection on other operating systems beyond Linux

[jmfernandez]

Right now, treecript uses information from /proc/cpuinfo in order to detect the type and topology of the CPUs.

But /proc/cpuinfo is only available on Linux. Other operating systems, like macOS, Windows or the different BSD variants have other ways to provide that information.

This issue is to document several ways to obtain the CPU information in these different operating systems.

[jmfernandez]

In Windows, in theory, the wmic cpu subcommand should be able to provide the information (see https://slimbook.com/en/blog/guides-2/post/how-to-know-the-cpu-model-of-your-slimbook-440). Also, it can be obtained from PowerShell just using internal GetCimInstance --ClassName Win32_Processor command (see https://www.powershellgallery.com/packages/Get-SystemInfo/2.0.1/Content/Get-SystemInfo.ps1 ).

[jmfernandez]

In macOS, the sysctl machdep.cpu command can provide that info (see https://apple.stackexchange.com/a/352770)

[my_mac:~] admin% sysctl -a | grep machdep.cpu
machdep.cpu.max_basic: 22
machdep.cpu.max_ext: 2147483656
machdep.cpu.vendor: GenuineIntel
machdep.cpu.brand_string: Intel(R) Core(TM) i5-8210Y CPU @ 1.60GHz
machdep.cpu.family: 6
machdep.cpu.model: 142
machdep.cpu.extmodel: 8
machdep.cpu.extfamily: 0
.
.
.

machdep.cpu.core_count: 2
machdep.cpu.thread_count: 4
machdep.cpu.tsc_ccc.numerator: 134
machdep.cpu.tsc_ccc.denominator: 2

[jmfernandez]

In FreeBSD (and maybe OpenBSD) the command /sbin/sysctl hw should provide most of (if not all) the details (see https://stackoverflow.com/a/4088577 ):

$ /sbin/sysctl hw
hw.machine: i386
hw.model: Pentium III/Pentium III Xeon/Celeron
hw.ncpu: 1
hw.byteorder: 1234
hw.physmem: 665989120
hw.usermem: 604614656
hw.pagesize: 4096
hw.floatingpoint: 1
hw.machine_arch: i386
hw.aac.iosize_max: 65536
hw.an.an_dump: off
hw.an.an_cache_mode: dbm
hw.an.an_cache_mcastonly: 0
hw.an.an_cache_iponly: 1
hw.fxp_rnr: 0
hw.fxp_noflow: 0
hw.dc_quick: 1
hw.ste.rxsyncs: 0
hw.instruction_sse: 0
hw.availpages: 162432