Example.gramps and 1.7.2 grampsxml.dtd

[romjerome]

@romjerome

I was no more able to provide a Pull Request (github account and n check issues).

-GRAMPS_XML_VERSION_TUPLE = (1, 7, 1)  # version for Gramps 4.2
+GRAMPS_XML_VERSION_TUPLE = (1, 7, 2)  # version for Gramps 6.0

Ah, yes, sorry, maybe a pull request for this one (6.0 branch)?