Align MASVS Index to v2.1.0 of the standard

[otkd]

• Updated index to match the redefined groupings introduced in MASVS v2

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[otkd]

Marked as draft to give others opportunity to review groupings and make relevant additions

[jmanico]

This PR has conflicts. If its ready to go I'll take care of them. Please advise.

[otkd]

This PR has conflicts. If its ready to go I'll take care of them. Please advise.

@jmanico good to go, thanks!