Make InboundLedgers, LedgerConsensus abstract
[FOLD] Bug fix 1
[FOLD] Bug fix 2
[FOLD] Bug fix 3
[FOLD] Bug fix 4
[FOLD] Bug fix 5
[FOLD] Bug fix 6
[FOLD] Bug fix 7
[FOLD] Bug fix 8
[FOLD] Bug fix 9
[FOLD] Bug fix 10
[FOLD] Bug fix 11