Implement pure SQL interpreter

[stalniy]

• this interpreter should be part of a new package @ucast/sql (put it in packages/sql)
• it should support the same operators as js interpreter from @ucast/js
• it should allow to pass custom operators
• it should use createInterpreter function from @ucast/core to create interpret function
• the return value of interpret function is an array of 3 elements: [sql, params, joins]
• when it finds condition.field with dots inside it's a hint that this property may be a relation to another table. Using custom option joinRelation we can allow users to specify logic which determines whether it's a relation.
• submodule for objection
• submodule for sequelize
• submodule for mikro-orm
• submodule for TypeORM