Ticket #547: Check generated code script: erroneous unmodified code was detected

The script was expecting changed lines starting only with '+ ' or '- ', but it is not mandatory a blank space is present ('+#include ...', etc.). Change to only avoid the lines containing files names ('+++ /path/...' or '--- /path/...') but consider all other lines starting with +/- as changes

Contributes #547 (closed)