[I18N] Update translation terms from Transifex

addons/account/i18n/bg.po

addons/account/i18n/cs.po

addons/account/i18n/it.po

addons/account/i18n/th.po

addons/account/i18n/zh_CN.po

addons/account_analytic_default/i18n/bg.po

addons/account_asset/i18n/bg.po

addons/account_asset/i18n/cs.po

addons/account_bank_statement_import/i18n/cs.po

addons/account_check_printing/i18n/bg.po

addons/account_tax_cash_basis/i18n/cs.po

addons/account_tax_python/i18n/bg.po

addons/account_tax_python/i18n/cs.po

addons/account_voucher/i18n/bg.po

addons/account_voucher/i18n/cs.po

addons/analytic/i18n/bg.po

addons/auth_ldap/i18n/bg.po

addons/auth_oauth/i18n/cs.po

addons/barcodes/i18n/cs.po

addons/base_action_rule/i18n/bg.po