Added new 'example' type in ContributionType.java's enum
UI of 'Add Examples...' done
Contributed Examples tree displays in Examples window
Contribs now show in Example Manager
example folder no longer shows as node in JTree
Done taking modes into account when deciding whether/not to show examples
Updating display style of Examples Tree
Rename to Examples-Package
Using identifiers instead of names for modes
Changes to Add Example button's appearance
Changed Examples Tree structure
Added 'Add Examples...' option to Open Toolbar Menu
Redesigning 'Add Examples...' button
Solve old folders displaying
Fixed unwanted expansion of Add Examples button
Added function to colourize alternate rows of a JTree

Thus improving the Examples Tree UI appearance
Reduced Examples JTree's top border