update some FILES list files

src/FILES

@@ -1,13 +1,15 @@
 api/      - The code for the high-level wrapper API. Not needed if
             you use the lowel-level call-back/raw API.
 
+apps/     - Higher layer applications that are specifically programmed
+            with the lwIP low-level raw API.
+
 core/     - The core of the TPC/IP stack; protocol implementations,
             memory and buffer management, and the low-level raw API.
 
 include/  - lwIP include files.
 
-netif/    - Generic network interface device drivers are kept here,
-            as well as the ARP module.
+netif/    - Generic network interface device drivers are kept here.
 
 For more information on the various subdirectories, check the FILES
 file in each directory.

src/netif/FILES

@@ -2,30 +2,23 @@ This directory contains generic network interface device drivers that
 do not contain any hardware or architecture specific code. The files
 are:
 
-etharp.c
-          Implements the ARP (Address Resolution Protocol) over
-          Ethernet. The code in this file should be used together with
-          Ethernet device drivers. Note that this module has been
-          largely made Ethernet independent so you should be able to
-          adapt this for other link layers (such as Firewire).
+ethernet.c
+          Shared code for Ethernet based interfaces.
 
 ethernetif.c
           An example of how an Ethernet device driver could look. This
           file can be used as a "skeleton" for developing new Ethernet
           network device drivers. It uses the etharp.c ARP code.
 
-loopif.c
-          A "loopback" network interface driver. It requires configuration
-          through the define LWIP_LOOPIF_MULTITHREADING (see opt.h).
+lowpan6.c
+          A 6LoWPAN implementation as a netif.
 
 slipif.c
           A generic implementation of the SLIP (Serial Line IP)
           protocol. It requires a sio (serial I/O) module to work.
 
-lowpan6.c
-          6LoWPAN implementation
-
 ppp/      Point-to-Point Protocol stack
           The lwIP PPP support is based from pppd (http://ppp.samba.org) with
           huge changes to match code size and memory requirements for embedded
-          devices. Please read ppp/PPPD_FOLLOWUP for a detailed explanation.
+          devices. Please read /doc/ppp.txt and ppp/PPPD_FOLLOWUP for a detailed
+          explanation.