Clean up HeckeMiscInteger.jl

[joschmitt]

The behaviour of mod_sym is still open for debate.

[codecov]

Codecov Report

Attention: Patch coverage is 83.33333% with 23 lines in your changes missing coverage. Please review.

Project coverage is 87.06%. Comparing base (3e66d55) to head (e0b7461).
Report is 7 commits behind head on master.

Files with missing lines	Patch %	Lines
src/flint/fmpz.jl	83.21%	23 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1848      +/-   ##
==========================================
+ Coverage   86.19%   87.06%   +0.86%     
==========================================
  Files          98       98              
  Lines       36210    40661    +4451     
==========================================
+ Hits        31212    35400    +4188     
- Misses       4998     5261     +263     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

[fingolfin]

Thanks

[fingolfin]

This is not really specific to ZZRingElem. I wonder if we should have a src/generic.jl file or perhaps src/generic dir in which we move such "generic" code (I think we have more examples in this vein).

Anyway, also OK by me to move it here for now. Just food for thought (since you've been touching many of these files, you probably have a better feeling than me whether this idea has merit or not)

[joschmitt]

There are some functions where it is not really clear, where they should go. In the end, I wouldn't know where I would search for a generic powering function, so I would need git grep anyway...