Fix typos in javadoc of ObjectId.equals()

Change-Id: Ic2503a2c3c616934d923937fdf8ceb4ae57b7028
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

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

@@ -111,16 +111,16 @@ public class ObjectId extends AnyObjectId implements Serializable {
 	}
 
 	/**
-	 * Compare to object identifier byte sequences for equality.
+	 * Compare two object identifier byte sequences for equality.
 	 *
 	 * @param firstBuffer
 	 *            the first buffer to compare against. Must have at least 20
-	 *            bytes from position ai through the end of the buffer.
+	 *            bytes from position fi through the end of the buffer.
 	 * @param fi
 	 *            first offset within firstBuffer to begin testing.
 	 * @param secondBuffer
-	 *            the second buffer to compare against. Must have at least 2
+	 *            the second buffer to compare against. Must have at least 20
-	 *            bytes from position bi through the end of the buffer.
+	 *            bytes from position si through the end of the buffer.
 	 * @param si
 	 *            first offset within secondBuffer to begin testing.
 	 * @return true if the two identifiers are the same.