SEI: Insert buffering period and picture timing SEI messages

The buffering period SEI message is inserted for every key frame and the
picture timing SEI is inserted for every frame. The commit also computes the
HRD parameters as well as HRD Timing parameters that are calculated using the
delay components(cpb removal delay and dpb output delay) carried in these
SEI messages. HRD parameters can be signalled by enabling --hrd.
SEI: only setup SEIPictureTiming fields which will be coded
TComSlice: nit - use bools to initialize bools
whitespace clean-up
x265.h, data declaration alignment
cli: seperate new lossless options, make --lossless description more concise

try to avoid having the --lossless line wrap
xp: avoid compiler warning from GCC-MinGW

MSVC gives a warning at link time if this file is empty, so I added a useless
variable to the file. GCC-MinGW issues a compile time warning about this
unused variable.
qp: remove Encoder::m_useLossless.

This patch removes confusion between Encoder::m_useLossless and x265_param::bUseLossless.
m_useLossless was set whenever qp = 0, and used in TComSPS. qp = 0  is still a valid
encoder option.
lossless: disable rate control, force QP=4

strangely enough, using QP=4 gives better lambda for lossless ME and RD
decisions
lossless: report compression ratio, disable distortion metrics
lossless: do not allow CQP to adjust QP for I/B when encoding lossless
param: only log psy-rd if it is enabled
Added tag 1.1 for changeset ae9609aeebdc
Merge with stable