Allow configurabe max_expansions on wildcard interval

[mattweber]

Is your feature request related to a problem? Please describe.
It is currently impossible to change the max expansions setting on a wildcard interval even though lucene allows it.

Describe the solution you'd like
Add a max_expansions setting in turn uses the lucene Intervals.wildcard(BytesRef wildcard, int maxExpansions) api. Default's can stay as-is but this would give the user ability increase the expansions. Even if the user goes crazy with this setting it is still further protected by lucene BooleanQuery.getMaxClauseCount().

Describe alternatives you've considered
Making intervals pluggable so users can create the own wildcard interval exposing this setting. I would love to see this but might not be needed if you expose more of the lucene interval functionality.

Additional context
Intervals are future and users wishing to migrate from a multi term span query would need this option.

[mattweber]

BTW, I am willing to do this work if it has a chance of being accepted.