[FIX] *: correct typos, improve wording

addons/account_tax_python/__manifest__.py

addons/hr_fleet/__manifest__.py

addons/hr_holidays_attendance/__manifest__.py

addons/l10n_at/__manifest__.py

addons/l10n_br/__manifest__.py

addons/l10n_hu/__manifest__.py

addons/l10n_jp/__manifest__.py

addons/pos_discount/__manifest__.py

addons/pos_epson_printer/__manifest__.py

addons/pos_epson_printer_restaurant/__manifest__.py

addons/pos_hr/__manifest__.py

addons/pos_restaurant/__manifest__.py

addons/pos_sale/__manifest__.py

addons/product_matrix/__manifest__.py

addons/sale_product_configurator/__manifest__.py

odoo/addons/base/i18n/base.pot

odoo/addons/base/models/ir_qweb_fields.py