Display request duration and request size

[JPFrancoia]

Hi,

Really great tool :) it replaced vial-http for me (the project seems kinda dead). One thing that is missing though is a couple of important metrics for a request: its size, and its duration. With vial-http, these two metrics were displayed in the status bar.

Would it be possible to add that to vim-http-client? Not necessarily in the status bar, but displayed somewhere would already be super helpful.

Cheers!