cherry-pick Core PR#7744 to abort test instead of freezing up
cherry-pick Core PR#7744 to abort test instead of freezing up

This is a merge of bitcoin/bitcoin#7744 / MVF-Core PR#16.

Instead of freezing up qa tests, wallet.py will fail on some 32-bit platforms where wallet salvage operation sometimes fails due to unknown reasons.

See also: bitcoin/bitcoin#7463 about the -salvagewallet problem.

Core has decided to disable the salvage part of the test in bitcoin/bitcoin#8038 , we may implement a Skip() of this test on 32-bit or disable that test step in a similar way.
The wallet salvage problem is definitely unrelated to any fork programming.
marlengit/hardfork_prototype_1_mvf-bu,BTCfork/hardfork_prototype_1_mvf-bu,BTCfork/hardfork_prototype_1_mvf-bu,marlengit/hardfork_prototype_1_mvf-bu,marlengit/hardfork_prototype_1_mvf-bu,BTCfork/hardfork_prototype_1_mvf-bu,ftrader-bitcoinunlimited/hardfork_prototype_1_mvf-bu,ftrader-bitcoinunlimited/hardfork_prototype_1_mvf-bu,marlengit/hardfork_prototype_1_mvf-bu,BTCfork/hardfork_prototype_1_mvf-bu,marlengit/hardfork_prototype_1_mvf-bu,ftrader-bitcoinunlimited/hardfork_prototype_1_mvf-bu,ftrader-bitcoinunlimited/hardfork_prototype_1_mvf-bu,BTCfork/hardfork_prototype_1_mvf-bu,marlengit/hardfork_prototype_1_mvf-bu,BTCfork/hardfork_prototype_1_mvf-bu,ftrader-bitcoinunlimited/hardfork_prototype_1_mvf-bu,ftrader-bitcoinunlimited/hardfork_prototype_1_mvf-bu