now get_url defaults to module temp dir (#36218)

* now get_url and other modules default to module temp dir

also fixed 'bare' exception

* allow modules to work with older versions

* updated docs per feedback

lib/ansible/modules/files/blockinfile.py

@@ -159,7 +159,7 @@ from ansible.module_utils._text import to_bytes
 
 def write_changes(module, contents, path):
 
-    tmpfd, tmpfile = tempfile.mkstemp()
+    tmpfd, tmpfile = tempfile.mkstemp(dir=getattr(module, 'tmpdir', None))
     f = os.fdopen(tmpfd, 'wb')
     f.write(contents)
     f.close()