[Android] Minify and obfuscate the javascript and css.

This patch is to minify and obfuscate the javascript and css
files before doing packaging.
Integrate the yui compressor with the packaging tool.
Yui compressor was gotten from http://yui.github.io/yuicompressor/
The license is BSD.
Merge pull request #1485 from wuhengzhi/compress_js_css

[Android] Minify and obfuscate the javascript and css.
[Android] Add the application version in the package file name.

Web application developer requires the application version be added
in the package file name, this fix is to meet this requirement by adding
the handling process of the application version in the packaging tool for
shared mode and embedded mode.

BUG=https://crosswalk-project.org/jira/browse/XWALK-908