Ported mgmtsystem_action
Fix typo and pep8
Changes made for API v8
Removed pdb lines
Removed vim lines and fixed domain
Removed comments and commented code
Added tests and updated code to v8
Fix flake8 errors
Updated according to reviews
Removed case_close

It is used and only contains things from mgmtsystem_nonconformity
Removed blank line, flake8 not happy
Removed check for user_id as user_id cannot be null

When doing `case.user_id = None`, it will throw this error:

    IntegrityError: null value in column "partner_id" violates not-null
    constraint
Remove transition case_close and moved icon
Merge pull request #22 from savoirfairelinux/8.0-mgmtsystem_action

[REF] 8.0 mgmtsystem_action