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

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

The ApplicationInformation class will encapsulate Tizen application info, and
provides serialization method to transfer its data. An internal PkgMgrHandle
class is implemented to abstract appinfo and pkginfo handles, it also provides
methods to fetch different application information from them by using
pkgmgr-info/pkgmgr APIs.

In order to bind current ApplicationId to application extension, we will
translate the Crosswalk application ID to Tizen ApplicationId when it is
created.
[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.
Merge pull request #246 from seanlong/app_dev

[Application] Add Application API initial support (getAppInfo/getAppsInfo)