[FIX] Ignore leading zeroes when looking up domestic account numbers.

Fixes #16
[FIX] Anticipate wrong encoding in camt files
Flake8 on base_iban_bic_not_required
PEP8 on bank_statement_instant_voucher
PEP8 on account_payment_shortcut
PEP8 on account_iban_preserve_domestic
PEP8 on account_direct_debit
PEP8 on account_banking_uk_hsbc
PEP8 on account_banking_tests
PEP8 on account_banking_sepa_direct_debit
PEP8 on account_banking_sepa_credit_transfer
PEP8 on account_banking_payment_export
PEP8 on account_banking_payment_export
PEP8 on account_banking_partner_journal_account
PEP8 on account_banking_pain_base
PEP8 on account_banking_nl_triodos
PEP8 on account_banking_nl_multibank
PEP8 on account_banking_nl_ing_mt940
PEP8 on account_banking_nl_ing
PEP8 on account_banking_nl_girotel