Small refactoring in Collectibles service in order to make API code more simple.
Add TokenInstance interface with some common functions.
Implementations of TokenInstance for TokenMaster, Collectibles and Assets contracts.
Issue #11276
Adding new smart contracts and generated go files.
Deploy token owner function and master token address getter.
Adding deployer and privilegesLevel columns to community_tokens table.
Passing addressFrom to API calls.
Issue #11250