New methods for changing continent & country

Actual work done in MapPanel; stubs added to CountryData and
ContinentData as needed
Actually create a button for each country

Changed constructor to build a button for each country, as that got
overlooked somehow. Also some misc stub and comment changes.
Forgot comment
Init QuizRunner

moved quiz management skeleton from MapPanel to a new QuizRunner class
More QuizRunner work
Merge remote-tracking branch 'origin/Min' into Adam

Conflicts:
	src/project/MapPanel.java
Merge branch 'Adam'
Merge remote-tracking branch 'origin/Lauren'

Conflicts:
	src/project/MapPanel.java
Merge branch 'master' into Adam
Merge branch 'Adam' into Min

Conflicts:
	src/project/MapPanel.java
	src/project/StudentData.java
	src/project/WelcomeWindow.java