This also pins a specific release in the Travis test so future
API-breaking changins in crustls won't break curl builds.
Add RUSTLS documentation to release tarball.
Enable running tests for rustls, minus FTP tests (require
connect_blocking, which rustls doesn't implement) and 313 (requires CRL
handling).
Closes#6763
You'll find a mix of various documentation in this directory and
subdirectories, using several different formats. Some of them are not ideal
for reading directly in your browser.
If you'd rather see the rendered version of the documentation, check out the
curl website's documentation section for
general curl stuff or the libcurl section for
libcurl related documentation.