Support root arrays and nested arrays

[jjatria]

This patch makes it possible to run queries like the following:

[ first => 'Roger', last => 'Moore' ]
# Produces (first:"Roger" OR last:"Moore")

Although not the plan, after this was done I realised this also resolves #12, so that the below now works:

{ foo => [ [ 'bar', 'baz' ], [ 'car', 'caz' ] ] },
# Produces (((foo:"bar" OR foo:"baz") OR (foo:"car" OR foo:"caz")))