Subtypes of List or Opt are classified as root types

[Jesper Öqvist]

Subtypes of List or Opt should probably not be classified as root nodes. This can affect the missing inherited equation warnings. For example:

DynamicOpt: Opt;
inh boolean Opt.attr();

JastAdd will complain that attr lacks an equation because DynamicOpt is treated as a root type.

[Jesper Öqvist]

Opt and List subtypes can not be root nodes

fixes issue #190 (bitbucket)

→ <<cset 8d66b9efabba>>