gcc is upgraded to gcc-7.

Fixed accidental compiler flags concatenation for MSVC.

h2load measurement reveals that this strategy is 3 times faster than
the previous implementations.

Support for Windows / MinGW

fuzz: Fix typo (‘-fsanitize=adres’) in README.rst

Reduce libxml2 version requirement to 2.6.26

It's currently set at 2.7.7 but reducing this down to 2.6.26 allows
nghttp2 to be built on RHEL5

h2load: Print out h2 header fields with --verbose option

nghttpx: Send non-final response to HTTP/1.1 or HTTP/2 client only

Fix some typos in the nghttpx how-to doc

This reverts commit 59c78d58.

Just fix unreachable links and remove ndk...

Fix OCSP related error when building with BoringSSL