[tlbuild] wget-1.20.1 for tl19

[Karl Berry]

    I thought the TeX Live scripts were rewritten last year to use curl
    rather than wget on x86_64-darwin. 

They now prefer the system's curl (or wget), but still fall back to the
TL wget if there is nothing else.

    configure reported at the end that it
    could not find pkg-config.

The configure script should (IMHO) not require pkg-config. If you're up
for it, can you report the specifics to bug-wget at gnu.org? (Although I
won't be surprised if they don't consider it a problem.)

    I like to stick with the vanilla compile tools from Apple

Sure. --thanks, karl.