Changes related to creation of a modular backend in multiprecision [SyncWith: crypto3-multiprecision#70] #280

4 fail, 34 pass in 12s

20 files -   8 20 suites - 8 12s ⏱️ -32s
38 tests - 37 34 ✔️ - 38 0 💤 ±0 4 ❌ +1
86 runs - 74 78 ✔️ - 76 0 💤 ±0 8 ❌ +2

Results for commit bad7aa5. ± Comparison against earlier commit 54d68c0.