Refactor|libcore: Apply pimpl in RecordValue
libcore|DictionaryValue: Removing values by key
libcore|Observers: Querying if an observer is part of the audience
libcore|String: Added method to make only the first character uppercase
libcore|ScriptSystem: Removing native modules
libcore|ArrayValue: Cleanup in printing records

Add newlines before a RecordValue.
libcore: Added more audiences in Record and Variable

Observing added/removed members and getting value changes with
old/new values.
Refactor|libdoomsday: Added DEDRegister and used it for DED flags

DEDRegister maintains a Doomsday Script namespace that stores and
indexes definitions. DED flags are now stored in Defs.flags.
Definitions: Added the "Defs" native module, updated Def API