* add support for old missions API (aka "steps missions")
* config option to disable loading non SoD Data (used only for missions and achievements for now)
* make AuthenticateUser endpoint compatible with games that use e-mail as login
* add api keys for lands
* add GetGameCurrency endpoint
* allow create empty stores and add store "8" (empty)
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Co-authored-by: Robert Paciorek <robert@opcode.eu.org>
* add support for cache/store assets in partial mode
* use stream approach in assets proxy mode
* reduce memory usage on proxy big files
* reduce risk of game client timeouts on slow connection
