automated merge
update compile-fail/map-types.rs to use hashmap
cat modernization (cleanup of a run-pass test)
remove old StdMap trait

this has been replaced by core::container::Map
rm commented out std::map code from json module

it was replaced by LinearMap
rename map -> oldmap and mark it as deprecated

LinearMap is quite a bit faster, and is fully owned/sendable without
requiring copies. The older std::map also doesn't use explicit self and
relies on mutable fields.
oldmap: get rid of the legacy contains_key method
oldmap: implement core::container::Container
oldmap: implement core::container::Mutable
oldmap: remove the legacy each_value method
oldmap: get rid of the legacy each_key method
oldmap: remove legacy each method
oldmap: start conversion to explicit self