Maybe translate SGR control sequences of comint output into text properties.
Depending on variable `ansi-color-for-comint-mode' the comint output is
either not processed, SGR control sequences are filtered using
`ansi-color-filter-region', or SGR control sequences are translated into
text properties using `ansi-color-apply-on-region'.
The comint output is assumed to lie between the marker
`comint-last-output-start' and the process-mark.
This is a good function to put in `comint-output-filter-functions'.