[Application] Add Applicatin extension skeleton and getAppInfo/getAppsInfo support

The implementation is based on spec:
https://developer.tizen.org/dev-guide/2.2.0/org.tizen.web.device.apireference/tizen/application.html

The ApplicationInformation class retrieves the application information mainly
through pkgmgr-info APIs. To get current application ID, we get the Crosswalk
app ID from Runtime interface and translate to Tizen ApplicationId in extension
creation.
[Application] Add Application API example for getAppInfo/getAppsInfo

Application API needs to be run in an installed app context, so a manifest file
is also added.