Changed a word in the README.md

README.md

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 - Better implement the language-agnostic setup (make NumeralManager to read from a file, instead of having a separate .cpp file only with the "language_setup" function)
 - Error handling
 - Make the whole CLI interface (help/usage tooltip message, options to read a [list of] string[s] or a [list of] file[s], ...)
-- Proper CMake configuration instead of a modified version of a Makefile generated at start
+- Proper CMake configuration instead of a modified version of a Makefile generated at the beginning