Fixes #2399: Reformatting required in dimension file for better struc…

…ture (#5168)

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## Explanation
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  --> Fixes #2399 
This PR has restructured the dimens.xml files. The file is too large so
just rearranged the dimensions to form the groups on the base of their
name, so that we find all the the dimensions related to a particular
category at once with ease.

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Co-authored-by: Adhiambo Peres <[email protected]>