http://www.ibm.com/developerworks/cn/education/opensource/os-eclipse-ganymede-pt1/section6.html
http://popjxc.iteye.com/blog/901965
http://www.ralfebert.de/blog/eclipsercp/p2_updates_tutorial_36/
http://www.ralfebert.de/blog/eclipsercp/p2_updates_tutorial/
http://wiki.eclipse.org/Equinox/p2/Adding_Self-Update_to_an_RCP_Application
http://www.ralfebert.de/blog/eclipsercp/p2_updates_tutorial_36/