Bp shushiri rebase

added 27 commits

• 0bb393b5...bc029ee3 - 3 commits from branch master
• fe4b9a5f - Algorithm for computation of all exact covers added
• 48045c48 - Algorithm for computation of approximate covers added
• db5c3287 - Algorithm for computation of restricted approximate covers added
• 25ccc0b5 - small code changes
• 2eef1489 - NDApproxSuffixAutomaton moved to indexing
• 62d01d49 - NDApproxSuffixAutomaton removed from cover
• ee944a3e - Registration to aql2 added
• 9d28d24d - return type changed to LinearString
• 72b911ee - Fixed bug in distance computation
• b81c157e - Register some types for print/xml
• f563fedd - Rewrite cover unit tests to catch2
• 07482fda - Adapt to changes in data structures
• 1fa54389 - Cover speedup: References
• 2445af25 - Cover speedup: Fix set erase
• ce5fabc0 - Cover speedup: elgo epsilon
• e1b92afe - Cover speedup: Remove noop
• 73497301 - Cover speedup: Rewrite loops
• 4d56d964 - simplify and format ExactCovers
• 24dbb15a - simplify and format RestrictedApproxCovers
• 88f1472c - simplify and format ApproxCovers
• 9fbf893f - simplify and format NondeterministicApproximateSuffixAutomatonForHammingDistance
• 6192d262 - algo: Split NondeterministicExactSuffixEpsilonAutomaton into NFA and EpsilonNFA variants
• ff3d5972 - algo: Split...
• ff18f103 - Move covers to alib2algo

Compare with previous version

enabled an automatic merge when the pipeline for ff18f103 succeeds

merged