coala_modes.py: Warn for log_printer param
coala_modes.py: Warn for log_printer param

Warn if log_printer is used in mode_normal function.

Closes https://github.com/coala/coala/issues/4972

coala-analyzer/coala,SanketDG/coala,coala/coala,coala/coala,jayvdb/coala,coala/coala,coala-analyzer/coala,SanketDG/coala,jayvdb/coala,coala-analyzer/coala,jayvdb/coala,SanketDG/coala