fail-fast: report missing --relation and --attribute early and avoid crashing without any useful error message
af3df945b51f1f2623b755964a291621fedcf793 v0.8
8a0848b9008ab1fd6e0ecac7158475c300f6256c v0.9
5c7baffb2148001ab955afb5aaf4a605eece0149 v0.10
da48e9dd11f37705479bb3d40fbf086965c08b58 v0.11
4b9d3b4c6ff1e195cf4c97932b94f387937c10b5 v0.12
350f38b110e4336f14eb9f2db027676bf9721859 v0.13
27f0ffa712d9455b2559ce3ffef0ab4e08278df2 v0.14
c3672791b2e89c3a5caf9abca43ab666743bdc7a v0.15
33ada8ed2803bfdddec610cc6c3683257d352ac8 v0.16