I can create App Appages from Visual Studio 2013 using the wizard.

The resulting file is MyProject_Win8_1.1.1.3_x86_x64_arm_bundle.appxupload, which is great!
I can use the following command to create an .appxupload file for any platform.
msbuild mysolution.sln /property:Configuration="Release" /t:"myproject_Win8" /p:Platform="ARM" /m:4 /t:"Publish"
which leads to the creation of MyProject_Win8_1.1.1.3_ARM.appxupload
How can I tell msbuild to create all 3 platforms I need and create one .appxupload file that will contain all of them?
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