Implement power panel in gnome-usage

gnome-usage is a tool for informing users about system statistics and performance. This project aims to extend gnome-usage by implementing the power panel. Major objectives include development of the required infrastructure to measure individual application and hardware device power consumption and implementing the front end panel to display it. The measurement infra would be placed in a shared library so that other applications may also utilize it. By the end of this project, gnome-usage would represent significant utility for end users as a tool to identify major power consumers and for developers to monitor system resource consumption efficiently.