fix: change idel to idele and improve printing

[thofma]

As announced to you @fieker, here the renaming and some printing improvemens to make the notebook look nicer.

After I found out how to type an accent grave I was tempted to go with idèle, but I expected fierce resistance.

P.S.: Reference for the spelling is https://encyclopediaofmath.org/wiki/Id%C3%A8le and the citations in there.

[codecov]

Codecov Report

Attention: Patch coverage is 53.84615% with 12 lines in your changes missing coverage. Please review.

Project coverage is 81.84%. Comparing base (b9f564a) to head (45eda1c).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3859      +/-   ##
==========================================
- Coverage   81.84%   81.84%   -0.01%     
==========================================
  Files         580      580              
  Lines       79900    79906       +6     
==========================================
  Hits        65398    65398              
- Misses      14502    14508       +6     

Files	Coverage Δ
experimental/GModule/src/GaloisCohomology.jl	67.50% <53.84%> (-0.37%)	⬇️