Internal: streamline use of IndexClosedException when executing operation on closed indices

Single index operations to use the newly added IndexClosedException introduced with #6475. This way we can also fail faster when we are trying to execute operations on closed indices and their use is not allowed (depending on indices options). Indices blocks are still checked but we can already throw error while resolving indices (MetaData#concreteIndices).

Effectively this change also affects what we return when using one of the following apis: analyze, bulk, index, update, delete, explain, get, multi_get, mlt, term vector, multi_term vector. We now return `{"error":"IndexClosedException[[test] closed]","status":403}` instead of `{"error":"ClusterBlockException[blocked by: [FORBIDDEN/4/index closed];]","status":403}`.

Closes #6988