Port shrpx to nghttp2 use
fixup
shrpx: SPDY support in upstream connection
HttpServer: Fix left_connhd_len_ is not updated
shrpx: Send and receive client connection header
Rename shrpx as nghttpx superficially
nghttpx: Remove :version from http2 connection
nghttpx: Add HTTP/2.0 word in help message
NGHTTP2_SETTINGS_FLOW_CONTROL_OPTIONS: Check least significant bit only
Fix header compression bug, and perform always incremental indexing
Remove :version from downstream HTTP/2.0 request
Fix header compression (again)
Incremental indexing only when the entry size if less than threshold