Incorrect handling of qualifiers for pointers in typeAssignableTo

[krame505]

This should be a subsetting relation, but right now we are checking that all qualifiers are identical. This means that something like

char *a;
const char *b = a;

is considered an error, while this should really be legal. As a temporary workaround in the feature/templating branch, I am disabling checking of qualifiers on pointers completely.