Added ExpressionBuilder::nolike() method

While working on a project in which I'm using the Dbal QueryBuilder, I found that the API doesn't provide a notlike() method, which I definitely need. 
In the end, using the like() method I solve the problem, but in an ugly way(IMO): $qb->expr()->like('a.host NOT', $qb->expr()->literal('%.com'))

That's why I think there should exists the notlike() method in the API. 
Thoughts?