PojoBuilder New Feature Proposal

Added an AST transformation @PojoBuilder that creates for given provided Pojo class "with" methods that allow to set values on a Pojo together with the "build" method that allows to instantiate it.

Example:

POJO - Person
```
          class Person {
               String firstName
               String surName
           }            
```

PersonBuilder
```
          @PojoBuilder(forClass = Person)
          class PersonBuilder {
               
          }
```

Building
```
       def person = personBuilder.withFirstName("Robert").withSurName("Lewandowski").build()
```

Verification
```
       assert person.firstName == "Robert"
       assert person.surName == "Lewandowski"
```