Add missing @since tags

Change-Id: I9657125765716c874bb6ecf8844c34749cb3b069
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit/src/org/eclipse/jgit/diff/RenameDetector.java

 	 *            reader to obtain objects from the repository with.
 	 * @param cfg
 	 *            diff config specifying rename detection options.
+	 * @since 3.0
 	 */
 	public RenameDetector(ObjectReader reader, DiffConfig cfg) {
 		objectReader = reader.newReader();

org.eclipse.jgit/src/org/eclipse/jgit/lib/CheckoutEntry.java

 
 /**
  * Parsed information about a checkout.
+ *
+ * @since 3.0
  */
 public interface CheckoutEntry {
 

org.eclipse.jgit/src/org/eclipse/jgit/lib/Constants.java

 	/** Packed refs file */
 	public static final String PACKED_REFS = "packed-refs";
 
-	/** Excludes-file */
+	/**
+	 * Excludes-file
+	 *
+	 * @since 3.0
+	 */
 	public static final String INFO_EXCLUDE = "info/exclude";
 
 	/** The environment variable that contains the system user name */

org.eclipse.jgit/src/org/eclipse/jgit/lib/ReflogEntry.java

 
 /**
  * Parsed reflog entry
+ *
+ * @since 3.0
  */
 public interface ReflogEntry {
 

org.eclipse.jgit/src/org/eclipse/jgit/lib/ReflogReader.java

 
 /**
  * Utility for reading reflog entries
+ *
+ * @since 3.0
  */
 public interface ReflogReader {