Container type of any currently not supported

[thisiscam]

i.e seq[any] is currently not supported due to the design choice we made.

In order to support container type of any, one have to either

1. supply many casts from and to the interface IPType
2. fill up with a corner type case of ptype any by implementing another generic list type

The second would be preferred over the first, since otherwise after ValueSummary transform using the first method will suffer greatly on performance