Added IsNonabelianSimpleGroup; removed bad implication IsSimpleGroup => IsAlmostSimpleGroup

[hulpke]

and use it in library wherever this is intended in place of IsSimpleGroup.

There were places in the code which uses IsSimpleGroup intending nonabelian simple. While thy did not cause obvious errors, it is cleaner to use a dedicated filter and will also inherit the IsAlmostSimpleGroup implication.

Release Notes:
Clarified definition and use of IsSimpleGroup to allow for abelian simple groups and introduced IsNonabelianSimpleGroup.

[codecov]

Codecov Report

Merging #3522 into master will decrease coverage by 12.01%.
The diff coverage is 53.12%.

@@             Coverage Diff             @@
##           master    #3522       +/-   ##
===========================================
- Coverage   85.45%   73.44%   -12.02%     
===========================================
  Files         696      534      -162     
  Lines      344887   267375    -77512     
===========================================
- Hits       294739   196370    -98369     
- Misses      50148    71005    +20857

Impacted Files	Coverage Δ
lib/gpprmsya.gi	69.24% <0%> (-17.2%)	⬇️
lib/grpperm.gi	86.7% <0%> (-4.15%)	⬇️
lib/factgrp.gi	53.45% <0%> (-29.2%)	⬇️
lib/grp.gd	100% <100%> (ø)	⬆️
lib/maxsub.gi	34.5% <100%> (-32.08%)	⬇️
lib/clashom.gi	39.43% <100%> (-42.1%)	⬇️
lib/grplatt.gi	33.22% <22.22%> (-44.82%)	⬇️
lib/fitfree.gi	50.97% <50%> (-8.79%)	⬇️
lib/morpheus.gi	52.13% <60%> (-32.94%)	⬇️
lib/gpfpiso.gi	55.67% <66.66%> (-23.18%)	⬇️
... and 398 more

[fingolfin]

Thanks, this is a good idea. I'd do it slightly differently, though, see suggestions.

[fingolfin]

I fixed the diff in the manual, tests are running again

[wilfwilson]

The Travis build has passed but GitHub doesn't seem to have realised, so I can't merge.

[coveralls]

Coverage decreased (-0.002%) to 85.282% when pulling bd4f9a0 on hulpke:fixes into 662a665 on gap-system:master.

[hulpke]

I've included the last suggestion and rebases, lets hope (indeed it did) Travis complies.