Specifying a schema (http/https) as part of a host definition will override the default port

Tested on: `logstash-filter-elasticsearch (3.6.0)`

Defining a connection schema will override the default port (`9200`) for a given host.

Scenario: Elasticsearch node bound to loopback/localhost:

* `hosts => ["localhost:9200"]` - works
* `hosts => ["localhost"]` - works
* `hosts => ["http://localhost"]` - doesn't work