Like or Not Like - that's where the question

New `Comparison::LIKE` and `Comparison::NOTLIKE` as alternative solution for #45 :dancer: 

Support next wildcard characters:
`%` - any character(s), any amount
`_` - any character, only one
`\%` - escape for `%`
`\_` - escape for `_`
``$like = $comparison->getOperator() === Comparison::LIKE;`` is enough. No need to use a ternary operator to turn a boolean into itself.