Added pt and zh-cn language dropdown to src/calc2/components/calculator.tsx and src/calc2/components/navigation-mobile.tsx. It seems that the pt language contributor forgot to add his entry there
Corrected the list of files to add dropdown entry in add language guide section of README.md
src/calc2/components/calculator.tsxandsrc/calc2/components/navigation-mobile.tsx. It seems that the pt language contributor forgot to add his entry there