Make travis builds quicker
Make travis builds quicker

Remove 32-bit platforms from build matrix.
And only run the chain comparison tool for one configuration.

adpg211/bitcoin-master,bitcoinclassic/bitcoinclassic,deadalnix/bitcoin,zander/bitcoinclassic,bitcoinclassic/bitcoinclassic,adpg211/bitcoin-master,deadalnix/bitcoin,deadalnix/bitcoin,zander/bitcoinclassic,bitcoinclassic/bitcoinclassic,bitcoinclassic/bitcoinclassic,deadalnix/bitcoin,bitcoinclassic/bitcoinclassic,adpg211/bitcoin-master,zander/bitcoinclassic,zander/bitcoinclassic,adpg211/bitcoin-master,zander/bitcoinclassic,deadalnix/bitcoin,bitcoinclassic/bitcoinclassic,adpg211/bitcoin-master,adpg211/bitcoin-master,zander/bitcoinclassic,deadalnix/bitcoin