* Lookups (operator[], at, find, contains, count, value, JSON pointers)
return the last member of a duplicate key, as materialize() and
parse() keep it.
* operator[] on a discarded view returns a discarded view instead of
throwing, so v["a"]["b"] is safe for a missing "a".
* operator[] and at() take any integer type (not only int and size_t),
fixing ambiguous calls with unsigned, long, std::int64_t, ...
* Fix the operator[] documentation, which claimed a discarded view for
a type mismatch where type_error.305 is thrown.
Signed-off-by: Niels Lohmann <mail@nlohmann.me>
Niels Lohmann
c7df23666f