DEP-5: Comment field

[Lars Wirzenius <liw@liw.fi>]

The Comment field has been suggested for DEP-5.

There is a pretty clear consensus that we want it. Thus, I propose this
to be added to the section explaining fields in the header (the
paragraph with Format etc):

         * **`Comment`**
           * Optional
           * Single occurrence per paragraph, can occur in each paragraph.
           * Value: formatted text, no synopsis
           * Description: This field can provide additional information. For
             example, it might quote an e-mail from the Debian ftpmaster team
             justifying why the license is acceptable to the main archive, or
             an explanation of how this version of the package has been forked
             from a version known to be DFSG-free, even though the current
             upstream version is not.

Comments on Comment?