add generating script and the first version of codec_ver.h
use WELS_LOG_ERROR as default trace level in console app
modify WELS_LOG_WARNING as the default trace level
Avoid rebuilds if the version header hasn't changed

When generating the version header, don't overwrite it if the
new version is identical to the old one.
add check for cabac_init_idc range in parsing
unify spsid for pic and add check for mb_qp_delta
Merge pull request #1648 from huili2/bugfix_cabacinitidc

add check for cabac_init_idc range in parsing
Merge pull request #1650 from huili2/bugfix_cabac_mbqpdelta

unify spsid for pic and add check for mb_qp_delta
Merge pull request #1638 from ruil2/default_trace

modify WELS_LOG_WARNING as the default trace level
Merge pull request #1634 from ruil2/trace

use WELS_LOG_ERROR as default trace level in console app
Merge pull request #1642 from mstorsjo/avoid-rebuilds

Avoid rebuilds if the version header hasn't changed
skip the git version hash in the header
Merge pull request #1603 from sijchen/add_ver1

add generating script and the first version of codec_ver.h
Merge remote-tracking branch 'upstream/master' into travis.osx