some documentation fixes after merging contrib and example apps

Signed-off-by: Simon Goldschmidt <goldsimon@gmx.de>

BUILDING

@@ -99,9 +99,21 @@ the lwIP root dir:
 The CMakeLists.txt will autoselect the correct port
 for your system (supported: Linux, Windows, Darwin).
 
+To configure the example app to your needs, you need to copy the file
+    contrib/examples/example_app/lwipcfg.h.example
+to
+    contrib/examples/example_app/lwipcfg.h
+and edit to your needs.
+
 Makefile based build system
 ===========================
 lwIP also maintains file lists for Makefile-based
 build systems. Look for Filelists.mk files
 in the source tree. We try to maintain them,
 but lwIP's mainly focused build system is CMake.
+
+MS Visual Studio
+================
+lwIP also provides basic support for MSVS in the win32 port
+folder under 'msvc'. We try to maintain these files,
+but lwIP's mainly focused build system is CMake.

CHANGELOG

@@ -12,6 +12,22 @@ HISTORY
   2018-10-02: Dirk Ziegelmeier
   * Integrate contrib repository into main lwIP rep, tag STABLE-2_1_0_RELEASE
 
+(STABLE-2.1.2):
+
+  ++ Bugfixes:
+
+  2018-11-21: Jens Nielsen
+  * netbiosns.c: fix expecting too large packet (bug #55069)
+
+  2018-11-19: Dirk Ziegelmeier
+  * smtp.c: fix compiling with strict C compatibility because of strnlen (bug #55034)
+
+  2018-11-12: Simon Goldschmidt
+  * tcp.c: fix overflow check in tcp_recved triggering invalid assertion (bug #55015)
+
+  2018-11-12: Simon Goldschmidt
+  * tcp.c: fix a bug in sending RST segments (sent from port 0)
+
 (STABLE-2.1.1):
 
   ++ Bugfixes:

contrib/examples/example_app/lwipcfg.h.ci

@@ -1,6 +1,6 @@
 /**
- * Additional settings for the win32 port.
- * Copy this to lwipcfg_msvc.h and make the config changes you need.
+ * Additional settings for the example app.
+ * Copy this to lwipcfg.h and make the config changes you need.
  */
 
 /* configuration for this port */

contrib/examples/example_app/lwipcfg.h.example

@@ -1,6 +1,6 @@
 /**
- * Additional settings for the win32 port.
- * Copy this to lwipcfg_msvc.h and make the config changes you need.
+ * Additional settings for the example app.
+ * Copy this to lwipcfg.h and make the config changes you need.
  */
 
 /* configuration for this port */

contrib/ports/win32/readme.txt

@@ -1,17 +1,17 @@
 lwIP for Win32
 
 This is an example port of lwIP for Win32. It uses WinPCAP to send & receive packets.
-To compile it, use the MSVC projects in the 'msvc' subdir or the Makefile in the 'mingw' subdir.
+To compile it, use the MSVC projects in the 'msvc' subdir, the CMake files, or the Makefile
+in the 'mingw' subdir.
 
-For both compilers:
-- the lwIP core repository must be in a folder "lwip" next to the "contrib" folder
+For all compilers/build systems:
 - you have to set an environment variable PCAP_DIR pointing to the WinPcap Developer's
   Pack (containing 'include' and 'lib')
-  alternatively, place the WinPcap Developer's pack next to the "lwip" and "contrib" folders:
+  alternatively, place the WinPcap Developer's pack next to the "lwip" folder:
   "winpcap\WpdPack"
 
-You also will have to copy the file 'lwipcfg_msvc.h.example' to
-'lwipcfg_msvc.h' and modify to suit your needs (WinPcap adapter number,
+You also will have to copy the file 'contrib/examples/example_app/lwipcfg.h.example' to
+'contrib/examples/example_app/lwipcfg.h' and modify to suit your needs (WinPcap adapter number,
 IP configuration, applications...).
 
 Included in the contrib\ports\win32 directory is the network interface driver