nghttp2: bump to 1.29.0

nghttp2: bump to 1.29.0

439b9b6c (tag: v1.29.0) Update manual pages
48498452 Bump up version number to v1.29.0, LT revision to 29:1:15
d30f3816 Update manual pages
4d1139f6 Remove SPDY
48f57407 nghttpx: Update doc
c1f14d73 Update manual pages
216f4dad nghttpx: Remove redundant check
a4e27d76 Revert "nghttpx: Use an existing h2 backend connection as much as possible"
2365f12e Fix CMAKE_MODULE_PATH
03f7ec0f nghttpx: Write API request body in temporary file
2056e812 nghttpx: Increase api-max-request-body
1ebb6810 nghttpx: Faster configuration loading with lots of backends
a3ebeeaf nghttpx: Fix crash with --backend-http-proxy-uri option
422ad1be Use NGHTTP2_REFUSED_STREAM for streams which are closed by GOAWAY
97f1735c Bump up version number to 1.29.0

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