Gracefully handle ^D and treat it like ^C.

[iamleot]

Previously EOF was not handled and pressing ^D leads to an EOFError exception
(for Unix muscle memory is usually handy to just exit via a ^D), e.g.:

% cvss_calculator
Interactive CVSS3 calculator

Attack Vector: Network | Adjacent | Local | Physical
Attack Vector: N/A/L/P ^D
Traceback (most recent call last):
  File "/usr/pkg/bin/cvss_calculator-2.7", line 11, in <module>
    load_entry_point('cvss==1.7', 'console_scripts', 'cvss_calculator')()
  File "/usr/pkg/lib/python2.7/site-packages/cvss/cvss_calculator.py", line 42, in main
    vector_string = ask_interactively(version, args.all, args.no_colors)
  File "/usr/pkg/lib/python2.7/site-packages/cvss/interactive.py", line 98, in ask_interactively
    input_value = string_input().upper()
EOFError

Handle EOFError exception in the same way of KeyboardInterrupt.

[skontar]

Thanks!

[iamleot]

Hello Stanislav, Stanislav Kontár writes:

Thanks!

Thank you for quickly merging it! Keep up the good work!