equivalence between exponential funcitons in stdlib and mca

[t6s]

Motivation for this change

Rtrigo_def.exp in stdlib and expR are equal.

Checklist

• added corresponding entries in CHANGELOG_UNRELEASED.md

• added corresponding documentation in the headers

Reference: How to document

Merge policy

As a rule of thumb:

• PRs with several commits that make sense individually and that
  all compile are preferentially merged into master.
• PRs with disorganized commits are very likely to be squash-rebased.

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[affeldt-aist]

A definitely needed addition!

[affeldt-aist]

ah, we might need to adjust dependencies between packages maybe

[t6s]

What a compression rate (in the proof script) 😮 Thanks!

[proux01]

ah, we might need to adjust dependencies between packages maybe

If using topology, the result should be in file Rstruct_topology.v and not in Rstruct.v.

[affeldt-aist]

ah, we might need to adjust dependencies between packages maybe

If using topology, the result should be in file Rstruct_topology.v and not in Rstruct.v.

Indeed!