Support for index/search large numeric field

Currently if an number is larger than Long.MAX_VALUE, we can't index/search that in lucene as a number. For example, IPv6 address is an 128 bit number, so we can't index that as a numeric field and do numeric range query etc.

It would be good to support BigInteger / BigDecimal

I've tried use BigInteger for IPv6 in Elasticsearch and that works fine, but there are still lots of things to do
https://github.com/elasticsearch/elasticsearch/pull/5758