Add option to strip non-printable characters from the log output

[CullenMoMullen]

Currently any non-printable characters are written to the serial log. For instance escape sequences for color information. They show up in the log as unrecognizable characters. It would be nice to have the option of stripping these from the log file, but keeping them for display in the terminal.

[blardyblar]

I would also like this, as it would be very handy for my needs as well.

I can work on this, but my question is do you think the right way to go is have a separate menu option for this, File -> Save ASCII File? Looking at the code, that's the easiest way to add it without adding another dialog box where you have to choose if you want RAW or ASCII every time (which seems annoying / dumb)

For my use, I just want to remove all characters < 0x20 except 0x0A (LF) and 0x0D (CR), but it sounds like the original requestor also wants ANSI escape sequences removed - is there anything else I'm not thinking about that should be removed as well?

[blardyblar]

I coded up adding a new menu entry for Save ASCII File and stripping out any control characters other than 0x0D and 0x0A, but I haven't implemented any kind of ANSI escape code removal yet. I will do a PR when I add that