expose the spring settings interface to unitsync

[BrainDamage]

this would:
- prevent lobbies/settings tools to include lots of different libraries to handle the different ways that spring stores the settings in the different OS
- every settings tool / lobby / autohost will be able to benefit from it
- will be as cross platfrom as spring
- will allow engine devs to operates changes / additions to the settings code/parameters with little to nothing change for the setting tool maintainers
- allow spring to pass default settings for values
- allow spring to pass ranges from values
- automatically pass the paramters list

thoughts ?