[FIX] invoice_webkit - add rate label (lp:c2c-addons/6.1  rev 79)
[FIX] invoice_webkit - add rate label
(lp:c2c-addons/6.1  rev 79)

vrenaville/account-invoice-reporting,Eficent/account-invoice-reporting,amoya-dx/account-invoice-reporting,massot/account-invoice-reporting,raycarnes/account-invoice-reporting,hurrinico/account-invoice-reporting,charbeljc/account-invoice-reporting,Endika/account-invoice-reporting,damdam-s/account-invoice-reporting