Application tests for requestHandler

[mbollmann]

Originally reported by: Marcel Bollmann (Bitbucket: mbollmann, GitHub: mbollmann)

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We should rigorously test all AJAX requests that we expect the requestHandler to handle, so we can be sure that changes on the server-side code doesn't break any expected client-side functionality.

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• Bitbucket: https://bitbucket.org/mbollmann/cora/issue/67

[mbollmann]

Original comment by Marcel Bollmann (Bitbucket: mbollmann, GitHub: mbollmann):

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Add first, simple application test (re issue #67)