In AppVeyor I don't have to cleanup :-)

StefanScherer · StefanScherer · commit 32d736bb5499 · 2017-02-23T08:40:13.000+01:00
diff --git a/webserver/build.bat b/webserver/build.bat
@@ -1,5 +1,4 @@
 docker build -t webserverbuild -f Dockerfile.build .
-docker rm -f webserverbuild
 docker create --name webserverbuild webserverbuild
 mkdir tmp
 docker cp webserverbuild:/code/webserver.exe tmp

Original file line number	Diff line number	Diff line change
`@@ -1,5 +1,4 @@`
`1`	`1`	`docker build -t webserverbuild -f Dockerfile.build .`
`2`		`-docker rm -f webserverbuild`
`3`	`2`	`docker create --name webserverbuild webserverbuild`
`4`	`3`	`mkdir tmp`
`5`	`4`	`docker cp webserverbuild:/code/webserver.exe tmp`