Log Message:
Update to 1.7, based on PR 44014 from Aleksey Cheusov.
Set LICENSE.

Major changes in upstream

        Temporary file names now include digits in addition to letters.
        mktemp will now terminate after 2*N^62 attempts, where N
            is the number of Xs in the template.  Previously it would try
            forever.
        Fixed UTF8 formatting of the grave accent character in the manual.