Notification type error should be rendered in patternfly as danger

[skateman]

The notification backend operates with the levels success, error, warning and info, however, PatternFly has success, danger, warning and info. We missed this inconsistency earlier so all the notifications with error levels appeared without the appropriate styling. I added a function in the frontend that converts the error to a danger so PatternFly will understand it.

Before:

After:

Testing:

Notification.create(:type => :automate_user_error, :initiator => User.first, :options => { :message => 'hello' })

https://bugzilla.redhat.com/show_bug.cgi?id=1489798

@miq-bot add_label bug, fine/yes

[miq-bot]

Checked commit skateman@57c2527 with ruby 2.3.3, rubocop 0.47.1, and haml-lint 0.20.0
0 files checked, 0 offenses detected
Everything looks fine. ⭐

[simaishi]

Fine backport details:

$ git log -1
commit 28af21bc3770628afdb90cac9ab3390ce3c4e5f5
Author: Martin Hradil <himdel@seznam.cz>
Date:   Tue Oct 17 15:27:21 2017 +0000

    Merge pull request #2426 from skateman/error-danger-notifications
    
    Notification type error should be rendered in patternfly as danger
    (cherry picked from commit e0b0998ea2411981252b0a39d18ad498f5de345f)
    
    https://bugzilla.redhat.com/show_bug.cgi?id=1503611