Auto merge of #8991 - alexcrichton:debug-curl-verison, r=Eh2406
Auto merge of #8991 - alexcrichton:debug-curl-verison, r=Eh2406

With debug HTTP mode log curl's version

This will hopefully help any future reports where we're trying to
figure out what's going on with possible different versions of the
`curl` library.

rust-lang/cargo,rustyhorde/cargo,eminence/cargo,rustyhorde/cargo,eminence/cargo,rust-lang/cargo,nipunn1313/cargo,rustyhorde/cargo,rustyhorde/cargo,rust-lang/cargo,eminence/cargo,eminence/cargo,nipunn1313/cargo,rust-lang/cargo,nipunn1313/cargo,nipunn1313/cargo