#10 Improved type checking for varslots

[Thomas Friedrichsmeier]

Currently type-checking in varslots is probably
too strict. For instance there are a lot of numeric
types that don't currently get accepted as
numeric in the varslot (e.g. "AsIs" inside a
data.frame). Given the vast number of R
classes, this may not be trivial.

[Thomas Friedrichsmeier]

This is now tracked at https://bugs.kde.org/show_bug.cgi?id=357375 .