docs: mention that a foreground color can be bright

Also replace some backslashed spaces because they hinder the
justification of the man page.

doc/man/nanorc.5

@@ -248,8 +248,9 @@ Save automatically on exit, don't prompt.
 .TP
 .B set titlecolor \fIfgcolor\fR,\fIbgcolor\fR
 Specify the color combination to use for the titlebar.
-Valid color names for foreground and background are:
-.BR white , \ black , \ red , \ blue , \ green , \ yellow , \ magenta ", and " cyan .
+Valid names for the foreground and background colors are:
+.BR white ", " black ", " blue ", " green ", " red ", " cyan ", " yellow ",  and " magenta .
+The name of the foreground color may be prefixed with \fBbright\fR.
 And either "\fIfgcolor\fR" or ",\fIbgcolor\fR" may be left out.
 .TP
 .B set unix

doc/texinfo/nano.texi

@@ -841,7 +841,8 @@ Save automatically on exit, don't prompt.
 @item set titlecolor @var{fgcolor},@var{bgcolor}
 Specify the color combination to use for the titlebar.
 Valid color names for foreground and background are:
-white, black, red, blue, green, yellow, magenta, and cyan.
+white, black, blue, green, red, cyan, yellow, and magenta.
+The name of the foreground color may be prefixed with 'bright'.
 And either @var{fgcolor} or @var{,bgcolor} may be left out.
 
 @item set unix