Fixed scoremeter readings limit check and playground controls

[imanshu03]

1. Added logic to check if our readings are within the specified lowerLimit and upperLimit as follows:

• If oldReading prop does not exists, set the sanitizedOldReading value to LOWER_THRESHOLD.
• If oldReading prop exists, check if its values is greater than upperLimit or less than lowerLimit and set the sanitizedOldReading value respectively to upperLimit or lowerLimit. If oldReading falls within the specified limit, set the sanitizedOldReading value to oldReading prop value.
• If reading prop value falls out of the specified limit range( greater than upperLimit or less than lowerLimit) then set the sanitizedReading value to sanitizedOldReading otherwise set it to reading prop value

2. Fixed storybook playground controls