Update README.txt

I dont know if this is because the OSCodePointData has changed its directory structure over the last four years since you created this or if it was just an oversight but the example suggests you point at the .\Data folder. If you do this then it finds 0 records as the current database structure stores the CSV files in .\Data\csv.

This pull simply updates the docs to reflect that:

Add \csv folder to CODEPOINT command line example