[ci skip] added example of complex build matrix for appveyor (usses <details>)
[ci skip] added example of complex build matrix for appveyor (usses <details>)

fniephaus/filetreeCI,dalehenrich/smalltalkCI,dalehenrich/smalltalkCI,hpi-swa/smalltalkCI,hpi-swa/filetreeCI,dalehenrich/smalltalkCI,hpi-swa/filetreeCI,peteruhnak/smalltalkCI,fniephaus/filetreeCI,hpi-swa/smalltalkCI,fniephaus/filetreeCI,peteruhnak/smalltalkCI,hpi-swa/filetreeCI,peteruhnak/smalltalkCI