Create add method for initialized collections

[junkfactory]

If the initial fields in the class are initialized with a collection, the generated builder generates addTo... method.

Given

class Person {
       private final List<Address> addresses = new ArrayList<>();
       private final Set<String> emails;

Generates an inner Builder

public static class Builder {
      private List<Address> addresses = new ArrayList<>();
      private Set<String> emails;

     public Builder addToAddresses(Address e) {
         this.addresses.add(e);
         return this;
     }

    public Builder emails(Set<String> emails) {
        this.emails = emails;
       return this;
    }
}