Add example code to Scopes docs in README
Add example code to Scopes docs in README

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johan--/ransack,vaski/ransack,Mario245/ransack,outstand/ransack,reinteractive/ransack,martndemus/ransack,avit/ransack,activerecord-hackery/ransack,AndrewSwerlick/ransack,Eric-Guo/ransack,laserlemon/ransack,roman-franko/ransack,amboxer21/ransack,nagyt234/ransack,mariorcardoso/ransack,guilleva/ransack