python-cryptography-vectors, python-ndg-httpsclient, python-prettytable: Update UPSTREAM_CHECK variables to allow for version checking

Signed-off-by: Derek Straka <derek@asterius.io>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>

meta-python/recipes-devtools/python/python-prettytable_0.7.2.bb

@@ -20,3 +20,6 @@ do_install_append() {
         chmod 644 "${f}"
     done
 }
+
+UPSTREAM_CHECK_URI = "https://pypi.python.org/pypi/PrettyTable/"
+UPSTREAM_CHECK_REGEX = "/PrettyTable/(?P<pver>(\d+[\.\-_]*)+)"