syntax: groff, man: colorize also \" tail comments and \# line comments

This fixes https://savannah.gnu.org/bugs/?68109.
Reported-by: G. Branden Robinson <g.branden.robinson@gmail.com>

syntax/groff.nanorc

@@ -17,7 +17,7 @@ color cyan start="\\(\\)?n\[" end="]"
 # Requests
 color brightgreen "^\.[[:blank:]]*[^[:space:]]*"
 # Comments
-color yellow "^\.\\".*"
+color yellow "(^\\#|(^\.)?\\").*"
 # References to strings
 color green "\\(\\)?\*(.|\(..)"
 color green start="\\(\\)?\*\[" end="]"

syntax/man.nanorc

@@ -24,7 +24,7 @@ color yellow "^\.(RS|RE|UR|UE|MT|ME|EX|EE|PD|DT)"
 color yellow "^\.(ad|bp|br|ce|de|ds|el|ie|if|fi|ft|ig|in|na|ne|nf|nh|ps|so|sp|ti|tr)"
 
 # Comments.
-color cyan "(^\.)?\\".*"
+color cyan "(^\\#|(^\.)?\\").*"
 
 # Trailing whitespace.
 color ,green "[[:space:]]+$"