Rucio client package imports rucio.common.schema which is not part of distribution
Motivation
----------
From Isabel:
```
cmd: rucio upload --scope user.itrigger --rse TRIUMF-LCG2_SCRATCHDISK /tmp/itrigger/itrigger/.alrb/testing/tester.NKHUnK/rucio/bash/rucioUpload
2020-04-06 18:30:38,129
INFO Preparing upload for file myFile.d314ec0d-6684-4e3f-8501-47467586e335.log
2020-04-06 18:30:38,293
INFO Successfully added replica in Rucio catalogue at TRIUMF-LCG2_SCRATCHDISK
2020-04-06 18:30:38,842
INFO Successfully added replication rule at TRIUMF-LCG2_SCRATCHDISK
2020-04-06 18:30:39,962
ERROR No module named schema
2020-04-06 18:30:39,963
ERROR 
Rucio exited with an unexpected/unknown error.
Please rerun the last command with the "-v" option to gather more information.
If you're sure there is a problem with Rucio itself, please followup at: https://github.com/rucio/rucio/issues
rucio upload dataset (bash)                                         [FAILED]
```
For some reason the schema module seems to be imported, which is not part of the client distribution.

Modification
------------
We can add it to the distribution, but for me it is not clear why this is even needed, so we should understand this first.

diff --git a/setup_rucio_client.py b/setup_rucio_client.py
index 9e8b99437..a5e5d507a 100644
--- a/setup_rucio_client.py
+++ b/setup_rucio_client.py
@@ -14,7 +14,7 @@
 #
 # Authors:
 # - Vincent Garonne <vgaronne@gmail.com>, 2014-2018
-# - Martin Barisits <martin.barisits@cern.ch>, 2017-2019
+# - Martin Barisits <martin.barisits@cern.ch>, 2017-2020
 
 import os
 import re
@@ -39,7 +39,7 @@ sys.path.insert(0, os.path.abspath('lib/'))
 COPY_ARGS = sys.argv[1:]
 NAME = 'rucio-clients'
 IS_RELEASE = False
-PACKAGES = ['rucio', 'rucio.client', 'rucio.common',
+PACKAGES = ['rucio', 'rucio.client', 'rucio.common', 'rucio.common.schema', 
             'rucio.rse.protocols', 'rucio.rse', 'rucio.tests']
 REQUIREMENTS_FILES = ['etc/pip-requires-client']
 DESCRIPTION = "Rucio Client Lite Package"
['setup_rucio_client.py']