Request#query and #query= using nested query through configuration
Request#body and #body= using nested query through configuration
Request#body= backing to ternary if
Applying Bruno Vicenzo commits
Changing use_nested_query attribute to query_builder

query_builder it's a flexible way to change the behaviour when building
request's query or body from Hashes.

Available options: [:flat, :nested]

Example:

    HTTPI.query_builder # => HTTPI::QueryBuilder::Flat (by default)
    HTTPI.query_builder = :nested # => HTTPI::QueryBuilder::Nested

You can also customize and set your own query builder. Example:

    class CustomBuilder
      def self.build(query)
        # query is a Hash and you have to return a String
      end
    end
    HTTPI.query_builder = CustomBuilder
Merge pull request #126 from savonrb/query_builder

Query builder, an option to flat or nested queries