[demo-express] Add config for ManifestDemo3 and ManifestDemo4 to support pack with longer version length
[demo-express] Add config for ManifestDemo3 and ManifestDemo4 to support pack with longer version length

- Add apk-version-opt attribute in suite.json for ManifestDemo3 and ManifestDemo4
- Use demo-ex-em.png of demo-express as the icon of demoexpress embiddingapi

BUG=https://crosswalk-project.org/jira/browse/XWALK-4296

yunxliu/demo-express,zhuyongyong/demo-express,kangxu/demo-express,zhuyongyong/demo-express,chunywang/demo-express,haoxli/demo-express,wanghongjuan/demo-express,kangxu/demo-express,yunxliu/demo-express,kangxu/demo-express,axinging/demo-express,kangxu/demo-express,wanghongjuan/demo-express,zhuyongyong/demo-express,chunywang/demo-express,zhuyongyong/demo-express,axinging/demo-express,chunywang/demo-express,wanghongjuan/demo-express,yunxliu/demo-express,haoxli/demo-express,haoxli/demo-express,axinging/demo-express,chunywang/demo-express,haoxli/demo-express,axinging/demo-express,yunxliu/demo-express,wanghongjuan/demo-express