Grace.Config_Files comment preserving details

[Stephen Leake <Stephe.Leake@nasa.gov>]

(See
http://java.sun.com/j2se/1.4.1/docs/api/java/util/Properties.html,
"load" method, and http://www.nongnu.org/Grace/config_files.html)

The Java Properties definition doesn't say anything about preserving
comments when writing the file. The current Config_Files requirement
says comments are preserved, but isn't detailed enough to say how it
works. David Koogler proposed some details, and I've added more,
to get the following proposed requirement:

    Comments are associated with a key, and are preserved thru open
    and flush. Comments are intended to guide manually editing the
    file. Consecutive whole line comments appearing before a key are
    associated with that key, and are written to the file in the same
    form as they were read in. Whole line comments separated by blank
    lines from any following key do not associate and are lost during
    writing.

(David also wants comments on the same line as a key/value pair, but
I've deleted that here).

Discussion?

-- 
-- Stephe