[tlbuild] asymptote-2.37 in source tree

[Simon]

On Mon, 2016-03-14 at 23:05 +0000, Karl Berry wrote:
> John made a new release of asy.  I updated Build/source/utils/asymptote.
> Give it a try if you like.

Built + tested OK

Somewhat irritating that you have to set an environmental variable to
get the right epswrite or successor. No cleverer way to achieve it?
Autowritten config file?

> Various other updates have happened to luatex et al.,
> thanks to Luigi, Akira, and all.

Doing main build now.

/////////////////

Simon