New AdTrue bidder

[haibau]

Type of change

• New bidder adapter

Description of change

add new adtrue bidder

• test parameters for validating bids

{
  bidder: 'adtrue',
  params: {
                  zoneId: '21423',
                  publisherId: '1234',
                  reserve: 0.2
                  }
}

• contact email of the adapter’s maintainer: ssp@adtrue.com
• official adapter submission

PR for update prebid dev-docs: prebid/prebid.github.io#2603