Table role restrictions

[jongund]

To me it seems the table element should be restricted to the roles:
table
grid
treegrid
none/presentation

While table could be used to build many other widgets, do we really want to encourage the practice?

[stevefaulkner]

@jongund While I agree, the argument in the past has been that we should not restrict unless necessary. Some research needs doing, but I would certainly support tightening up if use cases are not forthcoming.