Add Lift/Colift/SolveLinearSystemInAbCategoryOrFail

[zickgraf]

Changes contained in the PR:

1. The first commit is preparatory (we use DecideZeroRows/Columns in the second commit which would cause errors in the compiler). Merged as Allow to exclude operations from being resolved #681.
2. Lift/Colift/SolveLinearSystemInAbCategory now assume that a lift/colift/solution exists.
3. The operation MereExistenceOfWitnessPairForBeingCongruentToZero is added for Adelman categories.
4. I have looked at all places where Lift/Colift/SolveLinearSystemInAbCategory are called and have adjusted them.
5. I have not changed all existing implementations in categories (i.e. AddLift etc.), because these are still correct: If the input is valid according to the new specification, these implementations do not return fail in the old specification and thus everything is fine. However, I have adjusted some implementations where the tests need IsLiftable etc. (which cannot be derived from Lift etc. anymore and thus have to be added primitively).

Fixes #673.

@sebastianpos I think it would be a good idea if you could review the changes touching FreydCategoriesForCAP. All the "new" code is copied from somewhere else (e.g. the code in IsLiftable in GradedCategoryOfRows is copied from CategoryOfRows), so there is no need for an in-depth review, but I think it would be good if you could check that I have copied things from the correct place (i.e. it's easy to swap Lift and Colift by accident :D).

[codecov]

Codecov Report

Merging #678 (1bf0c85) into master (983e246) will decrease coverage by 0.24%.
The diff coverage is 61.22%.

❗ Current head 1bf0c85 differs from pull request most recent head 54bba6a. Consider uploading reports for the commit 54bba6a to get more accurate results

@@            Coverage Diff             @@
##           master     #678      +/-   ##
==========================================
- Coverage   69.86%   69.61%   -0.25%     
==========================================
  Files         275      275              
  Lines       37375    37591     +216     
==========================================
+ Hits        26111    26168      +57     
- Misses      11264    11423     +159     

Impacted Files	Coverage Δ
CompilerForCAP/gap/ResolveOperations.gd	100.00% <ø> (ø)
...recompiled_categories/MatrixCategoryPrecompiled.gi	74.14% <20.00%> (+4.38%)	⬆️
...esentationsForCAP/gap/ModulePresentationsForCAP.gi	74.70% <22.72%> (-8.88%)	⬇️
..._categories/OppositeOfMatrixCategoryPrecompiled.gi	44.40% <33.33%> (+1.09%)	⬆️
CAP/gap/DerivedMethods.gi	78.23% <89.65%> (+0.45%)	⬆️
CAP/gap/CategoryMorphisms.gd	100.00% <100.00%> (ø)
CAP/gap/MethodRecord.gi	81.72% <100.00%> (+0.17%)	⬆️
CompilerForCAP/gap/PrecompileCategory.gi	94.75% <100.00%> (+0.03%)	⬆️
CompilerForCAP/gap/ResolveOperations.gi	81.52% <100.00%> (ø)
LinearAlgebraForCAP/gap/LinearAlgebraForCAP.gi	84.91% <100.00%> (-0.96%)	⬇️
... and 22 more

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[sebastianpos]

I checked the changes to the Freyd package. They all look fine. As we discussed yesterday, I'll merge this PR.