copy: migrate `opts` to native kwargs

config: use the writefile() utility to create the sample hgrc This function uses a context manager.

config: migrate `opts` to native kwargs

clone: migrate `opts` to native kwargs

bundle: migrate `opts` to native kwargs

branches: migrate `opts` to native kwargs

branch: migrate `opts` to native kwargs

bookmark: migrate `opts` to native kwargs There are a bunch of callers for `ui.formatter()`, so convert to bytes only for that call.

archive: migrate `opts` to native kwargs I'm not sure how to handle migrating core APIs like `scmutil.match`, so kick that can down the road. (Plus it's used all over, so the callers need to be migrated first.)

backout: migrate `opts` to native kwargs It will take a bit to unwind `cmdutil.commit`, so there's a conversion to byteskwargs there, without changing the type of `opts` in this function. That's also useful to flag it as needing to be changed.

cmdutil: migrate `opts` on commitstatus() to native kwargs

cat: avoid round tripping **opts -> byteskwargs -> strkwargs Some internal users still want byteskwargs, so they are serviced in place. Once this pattern of changing types is eliminated everywhere, the remaining internal uses can be cleaned up individually (hopefully).