Import lwIP contrib rep

... from http://git.savannah.gnu.org/cgit/lwip/lwip-contrib.git/ into contrib/ subdir, STABLE-2_1_0_RELEASE tag
lwIP contrib is now officially frozen
TODO: Fix build

contrib/ports/win32/msvc/build_coverity.cmd

@@ -0,0 +1,26 @@
+@echo off
+rem Usage: pass the path to cov-build.exe (with trailing backslash, without the exe) as first parameter
+rem ATTENTION: this deletes the output folder "cov-int" and the output file "cov-int.zip" first!
+
+set devenv="%ProgramFiles%\Microsoft Visual Studio 10.0\Common7\IDE\devenv.exe"
+if not exist %devenv% set devenv="%ProgramFiles%\Microsoft Visual Studio 10.0\Common7\IDE\vcexpress.exe"
+if not exist %devenv% set devenv="%ProgramFiles(x86)%\Microsoft Visual Studio 10.0\Common7\IDE\devenv.exe"
+if not exist %devenv% set devenv="%ProgramFiles(x86)%\Microsoft Visual Studio 10.0\Common7\IDE\vcexpress.exe"
+set covbuild=%1cov-build.exe
+set covoutput=cov-int
+set zip7="c:\Program Files\7-Zip\7z.exe"
+
+pushd %~dp0
+
+if exist %covoutput% rd /s /q %covoutput%
+if exist %covoutput%.zip del %covoutput%.zip
+
+%covbuild% --dir %covoutput% %devenv% lwip_test.sln /build Debug || goto error
+
+if exist %zip7% goto dozip
+echo error: 7zip not found at \"%zip7%
+goto error
+:dozip
+%zip7% a %covoutput%.zip %covoutput%
+:error
+popd