Made CommandLineInterface._create_input_processor a private method.
Made CommandLineInterface._create_input_processor a private method.

ddalex/python-prompt-toolkit,niklasf/python-prompt-toolkit,jaseg/python-prompt-toolkit,jonathanslenders/python-prompt-toolkit,amjith/python-prompt-toolkit,melund/python-prompt-toolkit,ALSchwalm/python-prompt-toolkit