* I believe working around `br_sslio_*` isn't worth the effort as the
same functionality can be done manually with `*_buf` + `*_ack` which
is used by sslio internally. This will especially be useful when
wrapping Write/Read traits in std.
* Since both server and client contextes use `br_ssl_engine_context`,
writing the routines for it removes a lot of future headaches. The
engines shouldn't be used directly but will be exposed anyway for
special cases and for having more discoverable errors.
* The `bearssl-sys` crate is basically usable at this point.
* The `bearssl` crate itself needs a lot work before being usable. The
design needs heavy iterations, considerationg and love.
Aydin Mercan