[FEATURE] Localized node routing and consistent use of context path

This change adds a LocalizedFrontendNodeRoutePartHandler that can be
configured for sites using localization. A new strategy for getting
the locale chain from an identifier is added with
LocaleChainResolverInterface and a Settings based implementation.

For consistent use of content dimensions in nodes, several parts of Neos
are updated to use the context path consistently.

Controllers and services in Neos are updated to use the new methods
in the ContextInterface instead of directly accessing the node data
through NodeDataRepository.

Change-Id: I497987d1926724cb91143b1009598abddb191f85
Releases: master