Feature Request: Whitelist Mercurial HTTP headers

[zombiezen]

I would like to package Mercurial as a Sandstorm app. The Mercurial wire protocol sends most of its data using HTTP headers. They follow the pattern X-HgArg-N, where N is an integer greater than zero. Each header payload will be ~1KB by default, so you can pick an upper bound on how high you want N to be.

(I tried hacking around this by disabling this mode of operation, but it blows out the URL length quickly, and it doesn't appear to have a retry mechanism.)