Fix @since tags of new API added after 4.7.0

Change-Id: I356f71cdef8e23a9b06cf0a4079060a116b9ed27
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

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

 
 	/**
 	 * Move the edit region by the specified amount.
+	 *
 	 * @param amount
-	 *            the region is shifted by this amount, and can be
-	 *            positive or negative.
-	 * @since 4.7
+	 *            the region is shifted by this amount, and can be positive or
+	 *            negative.
+	 * @since 4.8
 	 */
 	public final void shift(int amount) {
 		beginA += amount;

org.eclipse.jgit/src/org/eclipse/jgit/merge/StrategyResolve.java

 		return new ResolveMerger(db, inCore);
 	}
 
+	/**
+	 * @since 4.8
+	 */
 	@Override
 	public ThreeWayMerger newMerger(ObjectInserter inserter, Config config) {
 		return new ResolveMerger(inserter, config);

org.eclipse.jgit/src/org/eclipse/jgit/merge/StrategySimpleTwoWayInCore.java

 		return newMerger(db);
 	}
 
+	/**
+	 * @since 4.8
+	 */
 	@Override
 	public ThreeWayMerger newMerger(ObjectInserter inserter, Config config) {
 		return new InCoreMerger(inserter);