How can I import a jpeg or png image into a paint layer (or whatever layer is the applicable one), so that I can use it as a template for my own drawing?

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I am using "Krita, Version 2.8 Pre-Alpha, Using KDE Development Platform 4.10.4" under Windows 7

Create a new image, then use Layer->New...->Import Layer... to create the paint layer. Then go to File->Create Template from Image...