[webapi] Remove vehicle old cases and create some new cases

- Old cases does not follow the latest spec, so remove them.
- Follow new spec, add 43 cases

Impacted TCs num(approved): New 43, Update 0, Delete 139
Unit test Platform: Tizen IVI
Tizen test result summary: Pass 4, Fail 39, Blocked 0
[usecase-wrt] Update AudioPolicy test step

[Detailed commit message (if have)]
Impacted TCs num(approved): New 0, update 1, deleted 0
Unit test platform: [tizen]
Unit test result summary:Pass 1, Fail 0,Block 0
Merge pull request #922 from linshen/shenlin/usecase/update-0918

[usecase-wrt] Update AudioPolicy test step
[wrt][xwalk-2540] Update the README description
Merge pull request #924 from wanghongjuan/wanghongjuan/wrt/xwalk-2540

[wrt][xwalk-2540] Update the README description
Update pack script to add pkg-version option for specifying package version

Signed-off-by: Hao yunfeix <yunfeix.hao@intel.com>
Merge pull request #928 from haoyunfeix/yunfei/update-pack-script-to-add-pkg-version-option

Update pack script to add pkg-version option for specifying package vers...
Merge pull request #919 from xinliux/xinliux/webapi/Vehicle-update

[webapi] Remove vehicle old cases and create some new cases
[misc]Add fullscreen tcs for web-mbat-tests

[Detailed commit message (if have)]
Impacted TCs num(approved): New 1, update 0, deleted 0
Unit test platform: [tizen]
Unit test result summary:Pass 0, Fail 1,Block 0
BUGID:https://crosswalk-project.org/jira/browse/XWALK-2577
[wrt]update const.py path for wrt-manifest-tizen-tests

[Detailed commit message (if have)]
Impacted TCs num(approved): New 0, update 4, deleted 0
Unit test platform: [tizen]
Unit test result summary:Pass 0, Fail 2,Block 1
Test create folder ok,block/fail by:
https://crosswalk-project.org/jira/browse/XWALK-2290
Merge pull request #930 from linshen/shenlin/update-manifest0919

[wrt] [WEBQA-150] update const.py path for wrt-manifest-tizen-tests
Merge pull request #929 from linshen/shenlin/misc-update-0919

[misc]Add fullscreen tcs for web-mbat-tests
[webapi][xwalk-2561] Update codes based on Chromium implement

- mp4a.40.8/mp4v.20.8 is also not supported in chromium 38, need use mp4a.40.2/mp4a.40 instead.
- Verified on Crosswalk 9.38.204.0

Impacted tests(approved): new 0, update 2, delete 0
Unit test platform: [Tizen IVI][Android]
Unit test result summary: pass 2, fail 0, block 0
[doc] Transfer pdf to md in doc directory
Merge pull request #934 from kangxu/kangxu/wrt/doc/addMD

[doc] Transfer pdf to md in doc directory
Merge pull request #933 from haoxli/haoxli/webapi/xwalk-2561-video

[webapi][xwalk-2561] Update codes based on Chromium implement