Add error handling to GetIndicesPointingToAlias.
In ES 0.90.0 /wrongname/_aliases returns { "error": "IndexMissingException[[wrongname] missing]",
"status": 404 } instead of an empty array (e.g. in ES 0.20.6).
Adding error handling after _aliases call, otherwise GetIndicesPointingToAlias returns
two indices "error" and "status".
Adding to integration test.