update windows parts

* document need for ninja-build package
* update contrib/windows.sh, remove -DCROSS_COMPILE option, set -e and set +x

contrib/windows.sh

@@ -1,4 +1,6 @@
 #!/bin/bash
+set -e
+set +x
 mkdir -p build-windows
 cd build-windows
 cmake -G Ninja -DCMAKE_EXE_LINKER_FLAGS=-fstack-protector -DCMAKE_CXX_FLAGS=-fdiagnostics-color=always -DCMAKE_TOOLCHAIN_FILE=../contrib/cross/mingw64.cmake -DBUILD_STATIC_DEPS=ON -DBUILD_PACKAGE=ON -DBUILD_SHARED_LIBS=OFF -DBUILD_TESTING=OFF -DWITH_TESTS=OFF -DNATIVE_BUILD=OFF -DSTATIC_LINK=ON -DWITH_SYSTEMD=OFF -DFORCE_LOKIMQ_SUBMODULE=ON -DSUBMODULE_CHECK=OFF -DWITH_LTO=OFF -DCMAKE_BUILD_TYPE=Release ..

readme.md

@@ -81,7 +81,7 @@ additional build requirements:
 
 setup:
 
-    $ sudo apt install build-essential cmake git pkg-config mingw-w64 nsis
+    $ sudo apt install build-essential cmake git pkg-config mingw-w64 nsis ninja-build
 
 building: