Revisit indices options and make default values consistent

[javanna]

We currently support different indices options within apis that execute against multiple indices: http://www.elasticsearch.org/guide/en/elasticsearch/reference/current/multi-index.html .

We should revisit these indices options and defaults for each api and try to make them less confusing and more consistent.

Also, the code that applies these options, more specifically MetaData#concreteIndices, could use some love :)

[colings86]

+1

[clintongormley]

See #14102