[RELEASE] Released version 1.5-dev16

Released version 1.5-dev16 with the following main changes :
    - BUG/MEDIUM: ssl: Prevent ssl error from affecting other connections.
    - BUG/MINOR: ssl: error is not reported if it occurs simultaneously with peer close detection.
    - MINOR: ssl: add fetch and acl "ssl_c_used" to check if current SSL session uses a client certificate.
    - MINOR: contrib: make the iprange tool grep for addresses
    - CLEANUP: polling: gcc doesn't always optimize constants away
    - OPTIM: poll: optimize fd management functions for low register count CPUs
    - CLEANUP: poll: remove a useless double-check on fdtab[fd].owner
    - OPTIM: epoll: use a temp variable for intermediary flag computations
    - OPTIM: epoll: current fd does not count as a new one
    - BUG/MINOR: poll: the I/O handler was called twice for polled I/Os
    - MINOR: http: make resp_ver and status ACLs check for the presence of a response
    - BUG/MEDIUM: stream-interface: fix possible stalls during transfers
    - BUG/MINOR: stream_interface: don't return when the fd is already set
    - BUG/MEDIUM: connection: always update connection flags prior to computing polling
    - CLEANUP: buffer: use buffer_empty() instead of buffer_len()==0
    - BUG/MAJOR: stream_interface: fix occasional data transfer freezes
    - BUG/MEDIUM: stream_interface: fix another case where the reader might not be woken up
    - BUG/MINOR: http: don't abort client connection on premature responses
    - BUILD: no need to clean up when making git-tar
    - MINOR: log: add a tag for amount of bytes uploaded from client to server
    - BUG/MEDIUM: log: fix possible segfault during config parsing
    - MEDIUM: log: change a few log tokens to make them easier to remember
    - BUG/MINOR: log: add_to_logformat_list() used the wrong constants
    - MEDIUM: log-format: make the format parser more robust and more extensible
    - MINOR: sample: support cast from bool to string
    - MINOR: samples: add a function to fetch and convert any sample to a string
    - MINOR: log: add lf_text_len
    - MEDIUM: log: add the ability to include samples in logs
    - REORG: stats: massive code reorg and cleanup
    - REORG: stats: move the HTTP header injection to proto_http
    - REORG: stats: functions are now HTTP/CLI agnostic
    - BUG/MINOR: log: fix regression introduced by commit 8a3f52
    - MINOR: chunks: centralize the trash chunk allocation
    - MEDIUM: stats: use hover boxes instead of title to report details
    - MEDIUM: stats: use multi-line tips to display detailed counters
    - MINOR: tools: simplify the use of the int to ascii macros
    - MINOR: stats: replace STAT_FMT_CSV with STAT_FMT_HTML
    - MINOR: http: prepare to support more http-request actions
    - MINOR: log: make parse_logformat_string() take a const char *
    - MEDIUM: http: add http-request 'add-header' and 'set-header' to build headers
diff --git a/VERSION b/VERSION
index a7d99e0..a3bf801 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1.5-dev15
+1.5-dev16