Merge https://github.com/kerrermanisNL/PDL
Merge met donna
Massive Bug Fixes
Merge https://github.com/zanax/PDL
CourseDetail Fix
Merge pull request #37 from zanax/master

CourseDetail Fix
fix in href
Merge met donna
myGrades and disableQuestion
Huge merge met Gijs.
Merge error fixes
ReviewTest/GradeTest/DB Queries
conflict fix
conflict fix
Merge https://github.com/kerrermanisNL/PDL

Conflicts:
	PDL/src/main/java/connection/DB.java
	PDL/src/main/java/controllers/reviewTest.java
Merge pull request #40 from zanax/master

DB conflict Fixes en viewTest en gradeTest
administrator panel
merge met niels
merge
Popular courses(NEW), dynamic images for courses(NEW), disenroll course(FIX)