created new build script for powershell

build.ps1

@@ -0,0 +1,18 @@
+
+$current_directory = "$(pwd.exe)"
+Set-Variable -Name GOPATH -Value "$HOME/go:$current_directory"
+
+# NOTE: The following commands assumes you have Git For Windows
+# installed, which comes with a bunch of GNU tools packaged for windows:
+Set-Variable -Name GIT_COMMIT -Value "$(git rev-list -1 HEAD)"
+Set-Variable -Name CANONICAL_VERSION -Value "$(cat.exe ./VERSION)-$(uname)"
+Set-Variable -Name VERSION_STRING -Value "$CANONICAL_VERSION-$GIT_COMMIT"
+
+Set-Variable -Name buildpath -Value "build/$(uname)/gostations.exe"
+
+go mod vendor
+go mod tidy
+
+go build -o "$buildpath" -ldflags "-X main.version=$VERSION_STRING"
+
+& $buildpath -v