New Rule for dangerous type casts

[tdellmann]

A dynamic type cast like x := something(*somethingElse[]) can cause a panic. Because this can be extremely dangerous there should be a lint rule for it.

This rule should trigger if

• a type ist dynamicly casted to a single value
• a type is dynamicly casted and the second response value (ok) is ignored
  • the first result can be checked for nil - so this might be nice to configure
• a dynamic type cast happens in a return statement

The alternative would be to always panic.recover() in bigger projects and just live with something as unsafe like

return ctx.Value("myCoolErrorChan").(chan err)