Previously, when the ExpectedException JUnit rule was used with
FilteredClassPathRunner a LinkageError would occur if any of
ExpectedException's methods that take a Hamcrest Matcher were called.
This was due to the FilteredClassLoader delegating loading of
org.junit classes to its parent but not org.hamcrest classes. This
resulted in JUnit classes loading one version of the Hamcrest class
and the test class loading another.

This commit ensures that both the JUnit classes and the test class
use the same version of Hamcrest classes by also delegating the
loading of org.hamcrest classes to FilteredClassLoader's parent.