Remove all global variables, and clean up tsnet and cmd/tailscale's usage.
This is in prep for using this package for the web API too (it has the
best package name).
RELNOTE=tailscale.com/client/tailscale package refactored w/ LocalClient type
Change-Id: Iba9f162fff0c520a09d1d4bd8862f5c5acc9d7cd
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Adds missing file from fc12cbfcd3.
GitHub was having issues earlier and it was all green because the
checks never actually ran, but the DCO non-Actions check at least did,
so "green" and I merged, not realizing it hadn't really run anything.
Updates #3802
Change-Id: I29f605eebe5336f1f3ca28ebb78b092dd99d9fd8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>