Use jd__path_to_string to make return path.
Wrap idiom for creating a constant iterator.
Note TODO.
Benchmark snapshot
Reorg.
Coverage for array vivification.

Make sure we can vivify empty, partially full and overfull arrays.
Add coverage for initialisation from null.
Make slice iterator adapt to array size.

It's wasteful to iterate the whole sequence if we're not vivifying and
the slice is larger than the array.
One-liner for consitency.
Remove redundant type set.
Skeleton for tree walk iter.
Macro for common parser cases.
First cut of walk iterator.
Some test coverage for walk iter.

Need to stringify paths properly...
Merge remote-tracking branch 'origin/master'

Conflicts:
	t/jsonpath.json