src: Add util::array_size
Add reserved bits to header and frames

Currently reserved bit is always set to 0.  The addition of reserved
bit is for future extension.
tests: Remove debug output
src: Add missing SETTINGS ID to debug output

SETTINGS_MAX_FRAME_SIZE and SETTINGS_MAX_HEADER_LIST_SIZE are 2
missing SETTINGS IDs and now they are shown correctly.
Update sphinx_rtd_theme
Bump up version number to 0.6.0 and LT revision to 5:0:0
Update man pages
Bump up version number to 0.6.1-DEV
src: Check availability of ENONET
Bump up version number to 0.6.1
Update man pages
Bump up version number to 0.6.2-DEV
Add nghttp2_option_set_recv_client_preface()

By default, nghttp2 library only handles HTTP/2 frames and does not
recognize first 24 bytes of client connection preface. This design
choice is done due to the fact that server may want to detect the
application protocol based on first few bytes on clear text
communication. But for simple servers which only speak HTTP/2, it is
easier for developers if nghttp2 library takes care of client
connection preface.

If this option is used with nonzero val, nghttp2 library checks first
24 bytes client connection preface. If it is not a valid one,
nghttp2_session_recv() and nghttp2_session_mem_recv() will return
error NGHTTP2_ERR_BAD_PREFACE, which is fatal error.
libevent-server: Use nghttp2_option_set_recv_client_preface()
Compile with android NDK r10b 32bit target

Android does not have _Exit.  We detect this and use _exit instead.
clang-3.4 has an issue around undefined reference to
__atomic_fetch_add_4, so we stick to gcc-4.8 for now.
Just link to github releases page for released versions
Replace auto_delete* with defer
nghttpx: Call upstream resume_read after sending pending request to backend

With the combination of HTTP/1 upstream and HTTP/2 downstream,
downstream tells SHRPX_NO_BUFFER while connecting to the backend
server.  Previously, we did not call upstream resume_read and upload
was blocked.  This commit now calls upstream resume_read to unblock.
This commit also remove pending output buffer size of Http2Session
when calculating downstream connection's buffer is full.  This is
desirable since we only operate resume_read by stream basis.
nghttpx: Add more handling situation where response ends before request
Fix memory leak around stream->data_item

Previously we missed the case where stream->data_item is not deleted
and it caused leak.  Now stream->data_item is properly deleted when
session is deleted.  We decided not to delete data_item in
nghttp2_stream_free() since we need nghttp2_session to decide whether
data_item should be deleted or not there.