Remove redundant check on indices[]

The Remove section independently checked the size of indices, but now that
it is being checked at the end of verification it is not needed inside the
Remove clause
Reconfigure tests to more accurately describe the scenarios

The reason this bug wasn't caught by the existing tests is because the old test for nullness
only validated against a cluster which had zero indices.  The null index is translated into "_all",
and since there are no indices, this fails because the index doesn't exist.

However, as soon as you add an index, "_all" resolves and you get the situation described in the
original bug report (but which is not tested by the suite).