Contract Improvements

[YashP16]

Contract name	Function name	Suggestion	Benefit
Farm	farmPauseSwitch	Update to toggleFarmPause	It will remove one if condition and it’s error (FarmAlreadyInRequiredState). And a parameter inside the function.
Farm	updateRewardData	Rename to updateRwdTokenManager as it only updates the manager and nothing else of reward data	The naming would be more accurate.
FarmRegistry	feeReceiver, feeToken, feeAmount, extensionFeePerDay	Can make these variables private/ internal because we have a getter function for this. Also we can make them as a struct to save some storage.	Reduced bytecode and storage usage.