Remove Stream signatures from open and save FileDialogs
Merge pull request #15 from jlewin/development

Remove Stream signatures from open and save FileDialogs
Remove deprecated Select Folder signature from file dialogs.
Remove deprecated Select Folder signature from file dialogs.
more async working.
Initial StaticData platform abstraction
Add LoadIcon helper function
Revise default StaticData manager naming
Refactor STL loading for reuse and consistency to support removal of filesystem based StaticData dependency
Remove all remaining ApplicationStaticDataPath dependencies
Revise IStaticData interface