keep a single copy of config-win32.h in version control repository.

maketgz and buildconf.bat updated to reflect this.

buildconf.bat

@@ -27,6 +27,11 @@ if not exist include\curl\curlbuild.h.dist goto end_curlbuild_h
 copy /Y include\curl\curlbuild.h.dist include\curl\curlbuild.h
 :end_curlbuild_h
 
+REM create src\config-win32.h
+if not exist lib\config-win32.h goto end_config_win32_h
+copy /Y lib\config-win32.h src\config-win32.h
+:end_config_win32_h
+
 REM setup c-ares git tree
 if not exist ares\buildconf.bat goto end_c_ares
 cd ares