The mock HTTP host at httpbin.org has been unstable recently, so
replace it with a fork at mockhttp.org. Run requests through a CORS
proxy for the Emscripten HTTP tests because mockhttp.org does not set
CORS headers.
Update instructions for building and running HTTP request tests with
the Emscripten build.
Add parameter for passing arbitrary headers along with analytics.
Remove sleep statements from Windows test program builds.
Set test program to refresh config less frequently to prevent a race
condition when refreshing is lagging.
Cocktail Frank
a7b5909ebc
