Highlighting trailing spaces

[Pavel Roskin <proski gnu org>]

Hello, Andrew!

I have noticed that you added highlighting for trailing spaces in C.  I
believe that your patch should be reverted, at least for the 4.6.0
release.  I don't want to see it reported like a bug.

Some people (myself included) use the internal editor to read other
people's code.  I don't want to fix minor sloppiness in the code I didn't
write.  Highlighting for trailing spaces reduces readability of the code.
If my job is to fix a bug and submit a minimal patch to the author, the
red tails will distract me from my job.