Array tables

[clord]

Toml has array sections:

[[a]]
x = 1
[[a]]
x = 2

which parses to the same thing as:

a = [{"x": 1}, {"x": 2}]

(confirm)

I don't want to tokenize runs of two brackets separately because they occur with their normal meaning elsewhere, e.g., nested array literals: x = [[1,2,3], [4,5,6]] so they will have to be parsed.

[pbrisbin]

Is this fixed by #18? The 1 toml-test failure left after that PR merges doesn't appear related to this class of input.