Fix unit tests

src/test/java/com/gitblit/tests/GitBlitSuite.java

 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.lib.RepositoryCache;
 import org.eclipse.jgit.lib.RepositoryCache.FileKey;
-import org.eclipse.jgit.storage.file.FileRepository;
+import org.eclipse.jgit.internal.storage.file.FileRepository;
 import org.eclipse.jgit.util.FS;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;

src/test/java/com/gitblit/tests/GitServletTest.java

 import org.eclipse.jgit.api.errors.GitAPIException;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.revwalk.RevCommit;
-import org.eclipse.jgit.storage.file.FileRepository;
+import org.eclipse.jgit.internal.storage.file.FileRepository;
 import org.eclipse.jgit.transport.CredentialsProvider;
 import org.eclipse.jgit.transport.PushResult;
 import org.eclipse.jgit.transport.RefSpec;

src/test/java/com/gitblit/tests/PushLogTest.java

 import java.io.IOException;
 import java.util.List;
 
-import org.eclipse.jgit.storage.file.FileRepository;
+import org.eclipse.jgit.internal.storage.file.FileRepository;
 import org.junit.Test;
 
 import com.gitblit.models.PushLogEntry;