Merge grazcoin 2 18 2014

    Merge changes to the mastercoin-tools core:
    update consensus checker with masterchest and mymastercoins sites
    fix consensus checker to really cross compare all listed sites
    add transactionVersion parsing
    add sell offer sub action parsing
    skip balance retrieval of unknown addresses
    update transaction version according to spec v0.4 https://github.com/mastercoin-MSC/spec/#transaction-definitions