[WIP] Add bulk tests to check presense of sphinxsearch indices

This PR adds a test that checks the presense of sphinxsearch indices as they should be present as defined in the db. It was made in order to avoid having a situation where we have layers released that need indices to be present.

If the layer has the attribute `selectbyrectangle` set to true, a featureidentify request should be possible

If the layer has the attribute `searchable` set to true, a featuresearch request should be possible

Note:
While writing this PR, I noticed that we already have a mismatch between db definitions and physical presense of indices. More in comments.