Stop sending X-Static-Large-Object headers

If we were to include this in a normal PUT, it would 400, but only if
slo is actually in the pipeline. If it's *not*, we'll create a normal
Swift object and the header sticks.

- This is really confusing for users; see the related bug.
- If slo is later enabled in the cluster, Swift starts responding 500
  with a KeyError because the client and on-disk formats don't match!

Change-Id: I1d80c76af02f2ca847123349224ddc36d2a6996b
Related-Change: I986c1656658f874172860469624118cc63bff9bc
Related-Bug: #1680083

swiftclient/service.py

@@ -1983,7 +1983,6 @@ class SwiftService(object):
                         } for d in segment_results
                     ])
 
-                    put_headers['x-static-large-object'] = 'true'
                     mr = {}
                     conn.put_object(
                         container, obj, manifest_data,

tests/unit/test_shell.py

@@ -714,7 +714,6 @@ class TestShell(unittest.TestCase):
             mock.ANY,
             headers={
                 'x-object-meta-mtime': mock.ANY,
-                'x-static-large-object': 'true'
             },
             query_string='multipart-manifest=put',
             response_dict={})