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/net_tools/basics/get_url.py

@@ -49,7 +49,8 @@ options:
   tmp_dest:
     description:
       - Absolute path of where temporary file is downloaded to.
-      - Defaults to C(TMPDIR), C(TEMP) or C(TMP) env variables or a platform specific value.
+      - When run on Ansible 2.5 or greater, path defaults to ansible's remote_tmp setting
+      - When run on Ansible prior to 2.5, it defaults to C(TMPDIR), C(TEMP) or C(TMP) env variables or a platform specific value.
       - U(https://docs.python.org/2/library/tempfile.html#tempfile.tempdir)
     version_added: '2.1'
   force:
@@ -338,18 +339,17 @@ def url_get(module, url, dest, use_proxy, last_mod_time, force, timeout=10, head
                 module.fail_json(msg="%s is a file but should be a directory." % tmp_dest)
             else:
                 module.fail_json(msg="%s directory does not exist." % tmp_dest)
-
-        fd, tempname = tempfile.mkstemp(dir=tmp_dest)
     else:
-        fd, tempname = tempfile.mkstemp()
+        tmp_dest = getattr(module, 'tmpdir', None)
+
+    fd, tempname = tempfile.mkstemp(dir=tmp_dest)
 
     f = os.fdopen(fd, 'wb')
     try:
         shutil.copyfileobj(rsp, f)
     except Exception as e:
         os.remove(tempname)
-        module.fail_json(msg="failed to create temporary content file: %s" % to_native(e),
-                         exception=traceback.format_exc())
+        module.fail_json(msg="failed to create temporary content file: %s" % to_native(e), exception=traceback.format_exc())
     f.close()
     rsp.close()
     return tempname, info
@@ -413,7 +413,7 @@ def main():
     if module.params['headers']:
         try:
             headers = dict(item.split(':', 1) for item in module.params['headers'].split(','))
-        except:
+        except Exception:
             module.fail_json(msg="The header parameter requires a key:value,key:value syntax to be properly parsed.")
     else:
         headers = None