Windows color

[mattn]

• replace ssh/terminal#IsTerminal with mattn/go-isatty#IsTerminal
• wrap os.Stdout with go-colorable.

[clach04]

Thanks for sharing this @mattn .! Bit-rot has set in; I have an experimental branch https://github.com/clach04/sift/tree/issue_92_windows_color where it merges this change with main, essentially replacing golang.org/x/term with github.com/mattn/go-colorable and github.com/mattn/go-isatty

1. This works for me with an out-of-the-box build, colors work correctly in CMD.exe 🎉
2. It also allows the Terminal to work when using --color flag, BUT without it it does NOT use color. So this works EXACTLY the same as current code, so no negative impact for Windows Terminal users
3. In a CMD.exe Using --color flag does not generate color, still get the ANSI escape sequences showing as garbage as described in Issue with color on windows platform #92
4. I've not tested this under Unix/Linux, etc.

This is likely not ready for prime time like this (as it changes some libraries) but this looks promising 😄 and if Unix works the same, then this may be worth reviewing further. I would love out of box color working for sift under Windows. The test fix from @mattn works well enough for me to be useful