Fixes#5652
This reworks and unifies HTTP client/transport management in Talos:
* cleanhttp is used everywhere consistently
* DefaultClient is using pooled client, other clients use regular
transport
* like before, Proxy vars are inspected on each request (but now
consistently)
* manifest download functions now recreate the client on each run to
pick up latest changes
* system CA list is picked up from a fixed locations, and supports
reloading on changes
Signed-off-by: Andrey Smirnov <andrey.smirnov@talos-systems.com>
This adds support for downloading the machine config over TFTP. This
will allow users to avoid having to setup an HTTP server, and use
whatever they are using for PXE.
Signed-off-by: Andrew Rynhard <andrew@andrewrynhard.com>
