Add JUnit to classpath.

Add to classpath the following entries:
 - JUnit: junit-4.11.jar
    - Sources: junit-4.11-sources.jar
    - Javadoc: junit-4.11-javadoc.jar
 - Hamcrest Core: hamcrest-core-1.3.jar
    - Sources: hamcrest-core-1.3-sources.jar
    - Javadoc: hamcrest-core-1.3-javadoc.jar