don't add an artificial ./ subdir due to how os.path.relpath works

this fixes stuff like og:urls of https://foo/./ or https://foo/./page
and also removes an extra layer of depth in the breadcrumb hierarchy,
just by suppressing the '.' in relpath output at the root of pages/

fixes #21

Signed-off-by: Brian S. Stephan <bss@incorporeal.org>

tests/instance/config.json

@@ -18,7 +18,7 @@
 				"level": "DEBUG",
 				"handlers": ["console"]
 			},
-			"incorporealcms.pages": {
+			"incorporealcms.ssg": {
 				"level": "DEBUG",
 				"handlers": ["console"]
 			}