Do not validate TTOR anymore
Summary: We can limit ourself to accept transaction in any order before the fork point.
Test Plan:
make check ./test/functional/test_runner.py -extended
Do full IBD
Reviewers: #bitcoin_abc, Fabien
Reviewed By: #bitcoin_abc, Fabien
Subscribers: teamcity, Fabien, schancel
Differential Revision: https://reviews.bitcoinabc.org/D2213