removing ClassReference as it has now been propagated
+ changes '@Builder' to '@Block'
+ ensures that only the top-most block has a return type
Allows blocks to have their own return types, but not from
the annotations, since we can't create the correct method
return type to accommodate it. The user must provide the
return type via the method.
[FLAPI-147] creates a wrapper `Start` block for every block
Annotations

+ support for arrays
+ support for varargs
+ use FQCN of type name when method signatures
Introduces a new @FlapiAnnotation meta-annotation, which
makes it easier to skip over Flapi's own annotations when
introspecting a block helper class.
+ refactors some of the annotation introspector's find methods
+ skip over methods which have no quantifier annotations
+ fixes the 'only one annotation allowed' error