Benchmarks should be grouped by operation

[carrutstick]

The point of the benchmarks is to compare different numerical libraries, so they should be formatted in a way that allows a user to see how long common operations take using different libraries.

[NickSeagull]

Mentioning @mdibaiee

[carrutstick]

If others agree I should have time on Sunday to do the reorganization.

[mdibaiee]

@carrutstick I'm in complete agreement, please tell me if you need any help anywhere in the process, and thank you 😁 👍