bumped version to 1.19.9.1.

travis-ci: upgraded OpenSSL to 1.1.1k. (openresty#743)

build-win32.sh: upgraded openssl to 1.1.1k.

bumped version to 1.19.3.1.

bumped version to 1.19.3.1 RC1.

upgraded LuaJIT to 2.1-20201012-2.

bumped version to 1.17.8.2.

tests: fixed tests to reflect component version bumps.

upgraded lua-resty-core to 0.1.18rc4.

win32/win64: upgraded pcre to 8.44.