javadoc tweaks

core/java/src/net/i2p/data/DataHelper.java

@@ -1526,7 +1526,7 @@ public class DataHelper {
 
     /**
      * Caller should append 'B' or 'b' as appropriate
-     * NOTE: formatDuration2() recommended in most cases for readability
+     * NOTE: formatSize2() recommended in most cases for readability
      */
     public static String formatSize(long bytes) {
         float val = bytes;

core/java/src/net/i2p/data/KeyCertificate.java

@@ -9,6 +9,8 @@ import net.i2p.crypto.SigType;
 /**
  * This certificate type gets its own class because it's going to be used a lot.
  *
+ * Format is: 2 byte sig type, 2 byte crypto type, excess sig data, excess crypto data.
+ *
  * The crypto type is assumed to be always 0x0000 (ElG) for now.
  *
  * @since 0.9.12