Decide and implement extra questions we wish to ask during Vinux install.

Ubuntu's installer Ubiquity has a plugin mechanism that can be used to extend the installer, to ask the user more questions. It would be useful if we used this plugin system to ask the user further questions about how they want their system configured. Some ideas include:

 * Ofer to install extra package sets from the internet, i.e the same package sets that would be offered via easy install.
 * Ask whether the user wants console speech enabled.
 * Let the user choose which desktop environment they wish to use, i.e Unity 2D, GNOME shell, etc.
 * Offer to configure the first user account with a different accessibility profile than what was selected at installation time. (This would require a bit more backend work, but is certainly possible.)