nghttp2: bump to 1.30.0

nghttp2: bump to 1.30.0

f0836c7e Update manual pages
25db178b Bump up version number to 1.30.0, LT revision to 29:2:15
1b6713e6 Update AUTHORS
c1a496cf nghttpx: Fix bug that h1 backend idle timeout expires sooner
e098a211 mruby: Fix bug that response header is unexpectedly overwritten
0ba4bf51 Merge pull request #1120 from dylanplecki/issue-1119-mruby-header-overwrite
6deee203 Fix #1119: Stop overwrite of first header on mruby call to env.req.set_header(..)
6761a933 Merge pull request #1105 from nghttp2/nghttpx-upgrade-scheme
5cc3d159 nghttpx: Add upgrade-scheme parameter to backend option
652f57e7 Merge pull request #1104 from nghttp2/allow-ping-after-goaway
acd6b40e Allow PING frame to be sent after GOAWAY
0fbb46ed Merge pull request #1101 from nghttp2/remember-pushed-links
6ad629de Merge pull request #1102 from nghttp2/fix-missing-alpn-validation
74754982 nghttpx: Fix missing ALPN validation (--npn-list)
a31a2e3b nghttpx: Remember which resource is pushed
a776b0db Merge pull request #1092 from nghttp2/define-103
cfd926f0 src: Define 103 status code
72f52716 Bump up version number to 1.30.0-DEV

Signed-off-by: Hans Dedecker <dedeckeh@gmail.com>