Witnesses 2.0

[leventeBajczi]

This PR enables witnesses 2.0, as well as fixes a parameter parsing problem uncovered in pre-runs.

[github-actions]

Benchexec test report for a selection of SV-Benchmarks (correct / incorrect / all):

task set	BOUNDED	CEGAR	HORN
Arrays	✅ (1 / 0 / 87) HTML/CSV	❓ (0 / 0 / 4) HTML/CSV	✅ (1 / 0 / 53) HTML/CSV
BitVectors	✅ (4 / 0 / 22) HTML/CSV	✅ (3 / 0 / 29) HTML/CSV	✅ (1 / 0 / 27) HTML/CSV
Combinations	❓ (0 / 0 / 40) HTML/CSV	❓ (0 / 0 / 39) HTML/CSV	❓ (0 / 0 / 40) HTML/CSV
Concurrency	❓ (0 / 0 / 156) HTML/CSV	✅ (7 / 0 / 44) HTML/CSV	❓ (0 / 0 / 153) HTML/CSV
ConcurrencySafety-NoOverflows	❓ (0 / 0 / 150) HTML/CSV	✅ (24 / 0 / 50) HTML/CSV	❓ (0 / 0 / 150) HTML/CSV
ControlFlow	✅ (3 / 0 / 33) HTML/CSV	✅ (3 / 0 / 55) HTML/CSV	❗ (31 / 17 / 66) HTML/CSV
ECA	❓ (0 / 0 / 30) HTML/CSV	❓ (0 / 0 / 30) HTML/CSV	❓ (0 / 0 / 30) HTML/CSV
Floats	❓ (0 / 0 / 17) HTML/CSV	✅ (7 / 0 / 22) HTML/CSV	❓ (0 / 0 / 34) HTML/CSV
Hardware	❓ (0 / 0 / 28) HTML/CSV	✅ (1 / 0 / 10) HTML/CSV	❓ (0 / 0 / 28) HTML/CSV
Heap	✅ (10 / 0 / 112) HTML/CSV	✅ (41 / 0 / 94) HTML/CSV	❗ (10 / 2 / 112) HTML/CSV
Loops	✅ (11 / 0 / 48) HTML/CSV	✅ (5 / 0 / 12) HTML/CSV	✅ (24 / 0 / 67) HTML/CSV
NoDataRace	❓ (0 / 0 / 163) HTML/CSV	❗ (39 / 5 / 71) HTML/CSV	❓ (0 / 0 / 165) HTML/CSV
ProductLines	❓ (0 / 0 / 342) HTML/CSV	❓ (0 / 0 / 333) HTML/CSV	❓ (0 / 0 / 333) HTML/CSV
Recursive	❓ (0 / 0 / 153) HTML/CSV	✅ (6 / 0 / 36) HTML/CSV	❓ (0 / 0 / 153) HTML/CSV
Sequentialized	✅ (2 / 0 / 30) HTML/CSV	✅ (3 / 0 / 31) HTML/CSV	✅ (3 / 0 / 30) HTML/CSV
XCSP	✅ (2 / 0 / 32) HTML/CSV	✅ (6 / 0 / 36) HTML/CSV	✅ (5 / 0 / 32) HTML/CSV