Add missing @since tags and missing javadoc

Change-Id: I8575797127fc96abea8af56f019ca39f5897486f
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/JGitTestUtil.java

 		FileUtils.delete(path);
 	}
 
+	/**
+	 * @param db
+	 *            the repository
+	 * @param link
+	 *            the path of the symbolic link to create
+	 * @param target
+	 *            the target of the symbolic link
+	 * @return the path to the symbolic link
+	 * @throws Exception
+	 * @since 4.2
+	 */
 	public static Path writeLink(Repository db, String link,
 			String target) throws Exception {
 		return FileUtils.createSymLink(new File(db.getWorkTree(), link),

org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/LocalDiskRepositoryTestCase.java

 	/** A fake (but stable) identity for committer fields in the test. */
 	protected PersonIdent committer;
 
-	/** A {@link SystemReader} used to coordinate time, envars, etc. */
+	/**
+	 * A {@link SystemReader} used to coordinate time, envars, etc.
+	 * @since 4.2
+	 */
 	protected MockSystemReader mockSystemReader;
 
 	private final List<Repository> toClose = new ArrayList<Repository>();

org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/MockSystemReader.java

 	 *
 	 * @param secDelta
 	 *            number of seconds to add to the current time.
+	 * @since 4.2
 	 */
 	public void tick(final int secDelta) {
 		now += secDelta * 1000L;

org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/RepositoryTestCase.java

 		return JGitTestUtil.writeTrashFile(db, name, data);
 	}
 
+	/**
+	 * Create a symbolic link
+	 *
+	 * @param link
+	 *            the path of the symbolic link to create
+	 * @param target
+	 *            the target of the symbolic link
+	 * @return the path to the symbolic link
+	 * @throws Exception
+	 * @since 4.2
+	 */
 	protected Path writeLink(final String link, final String target)
 			throws Exception {
 		return JGitTestUtil.writeLink(db, link, target);

org.eclipse.jgit.junit/src/org/eclipse/jgit/junit/TestRepository.java

 	 *            the MockSystemReader to use for clock and other system
 	 *            operations.
 	 * @throws IOException
+	 * @since 4.2
 	 */
 	public TestRepository(R db, RevWalk rw, MockSystemReader reader)
 			throws IOException {
 		return git;
 	}
 
-	/** @return current date. */
+	/**
+	 * @return current date.
+	 * @since 4.2
+	 */
 	public Date getDate() {
 		return new Date(mockSystemReader.getCurrentTime());
 	}

org.eclipse.jgit/src/org/eclipse/jgit/util/FileUtils.java

 	 * Create a symbolic link
 	 *
 	 * @param path
+	 *            the path of the symbolic link to create
 	 * @param target
-	 * @return path to the created link
+	 *            the target of the symbolic link
+	 * @return the path to the symbolic link
 	 * @throws IOException
 	 * @since 4.2
 	 */