path fixes and Windows python3 fix

Dockerfile.win

@@ -24,7 +24,7 @@ RUN mv my_init /sbin
 RUN ./bootstrap_env.sh
 RUN ./setup_system.sh
 
-RUN mkdir /home/www-data/nodes
+RUN mkdir -p /home/www-data/nodes
 RUN cp /app/config.ini /home/www-data/config.ini
 
 # thanks to github.com/phusion

bootstrap.bat

@@ -1,4 +1,4 @@
 @echo off
 
 SET mypath=%~dp0
-docker build --no-cache -f Dockerfile.win -t dune %mypath%
+docker build  -f Dockerfile.win -t dune %mypath%

dune.bat

@@ -1,3 +1,16 @@
 @echo off
+
 SET mypath=%~dp0
-python3 %mypath%\src\dune %*
+
+WHERE /q python3
+IF ERRORLEVEL 1 (
+   WHERE /q python
+   IF ERRORLEVEL 1 (
+      ECHO "Python/3 was not found, please install."
+      EXIT /B
+   ) ELSE (
+      python %mypath%\src\dune %*
+   )
+) ELSE (
+   python3 %mypath%\src\dune %*
+)