Added a flip counter to the home view for overall meals total

# Changes #

### Added digits.png - used for the total counter flipper.

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### Created new data class in Parse - *Counter*.
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### index.html ###
- Added **counter.js** file to be included script.

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### counter.js ###
- Created file to set/update the value of the total meals counter on the home view.
- Currently set to update every 1 minute - can be changed in *numRefreshIntervalMinutes*.
- Will pull the total from the first row in the **Counter** data class - should only ever be one record in this data class.

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### main.scss ###
- Added necessary styling to make the total counter work appropriately.