Rudder

When clicking save on technique editor, it doesn't do anything on ubuntu 16.04, with rudder 4.1 (may exist on earlier version of rudder as well)
(note that there are even an error message displayed)

[Thu Mar 23 10:45:06.479878 2017] [wsgi:error] [pid 2524:tid 139647299086080]   InsecureRequestWarning)
[Thu Mar 23 10:45:07.770212 2017] [wsgi:error] [pid 2524:tid 139647265515264] /usr/share/ncf-api-virtualenv/lib/python2.7/site-packages/requests/packages/urllib3/connectionpool.py:852: InsecureRequestWarning: Unverified HTTPS request is being made. Adding certificate verification is strongly advised. See: https://urllib3.readthedocs.io/en/latest/advanced-usage.html#ssl-warnings
[Thu Mar 23 10:45:07.770236 2017] [wsgi:error] [pid 2524:tid 139647265515264]   InsecureRequestWarning)
[Thu Mar 23 10:45:07.844008 2017] [wsgi:error] [pid 2524:tid 139647265515264] ERROR: Could not write technique 'test' from path /var/rudder/configuration-repository/ncf, cause is: Error while running post-hook command /var/rudder/configuration-repository/ncf/ncf-hooks.d/post.write_technique.rudderify.sh /var/rudder/configuration-repository/ncf test
[Thu Mar 23 10:45:07.844030 2017] [wsgi:error] [pid 2524:tid 139647265515264] INFO: Alternative source path added: /var/rudder/configuration-repository/ncf
[Thu Mar 23 10:45:07.844033 2017] [wsgi:error] [pid 2524:tid 139647265515264] Error: Unable to create Rudder Technique files related to ncf Technique test ([Errno 13] Permission denied: '/var/rudder/configuration-repository/techniques/ncf_techniques/test')
[Thu Mar 23 10:45:07.844035 2017] [wsgi:error] [pid 2524:tid 139647265515264] Traceback (most recent call last):
[Thu Mar 23 10:45:07.844036 2017] [wsgi:error] [pid 2524:tid 139647265515264]   File "/usr/share/ncf/tools/ncf_rudder.py", line 47, in write_one_technique_for_rudder
[Thu Mar 23 10:45:07.844038 2017] [wsgi:error] [pid 2524:tid 139647265515264]     write_technique_for_rudder(destination_path, metadata)
[Thu Mar 23 10:45:07.844039 2017] [wsgi:error] [pid 2524:tid 139647265515264]   File "/usr/share/ncf/tools/ncf_rudder.py", line 129, in write_technique_for_rudder
[Thu Mar 23 10:45:07.844041 2017] [wsgi:error] [pid 2524:tid 139647265515264]     os.makedirs(path)
[Thu Mar 23 10:45:07.844042 2017] [wsgi:error] [pid 2524:tid 139647265515264]   File "/usr/lib/python2.7/os.py", line 150, in makedirs
[Thu Mar 23 10:45:07.844044 2017] [wsgi:error] [pid 2524:tid 139647265515264]     makedirs(head, mode)
[Thu Mar 23 10:45:07.844045 2017] [wsgi:error] [pid 2524:tid 139647265515264]   File "/usr/lib/python2.7/os.py", line 157, in makedirs
[Thu Mar 23 10:45:07.844053 2017] [wsgi:error] [pid 2524:tid 139647265515264]     mkdir(name, mode)
[Thu Mar 23 10:45:07.844055 2017] [wsgi:error] [pid 2524:tid 139647265515264] OSError: [Errno 13] Permission denied: '/var/rudder/configuration-repository/techniques/ncf_techniques/test'

# ls -al /var/rudder/configuration-repository/techniques/ncf_techniques
total 12
drwxr-sr-x 2 root rudder 4096 Mar 23 09:20 .
drwxrwsr-x 9 root rudder 4096 Mar 23 09:20 ..
-rw-r--r-- 1 root rudder  128 Mar 23 09:20 category.xml