Simplification of class structure.

No longer has the chronographer package, as that package is redundant.
Save Event feature added.

Added feature to save and load events to disk in an xml file using
XStream. (Junit test included.) Additionally, modified name of
ChronographerMainMenuController to MainMenuController to save typing and
reduce extraneous info.
Saves Timelines

Saving and loading timelines to disk now possible. (Junit test
included.) Events are now saved to the correct directory. (Fixes bug in
previous commit.)
Add Events, GUI Alterations

Altered the GUI to allow for user event input and added event-addition
functionality to the program. Also includes XStream library files.
Merge pull request #2 from leanne73/xstream

Xstream looks good