Rails4: replace deprecated #connection from Issue model

DEPRECATION WARNING: #connection is deprecated in favour of accessing it via the class.

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012715
Rails4: replace deprecated #connection from IssueCustomField model

DEPRECATION WARNING: #connection is deprecated in favour of accessing it via the class.

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012716
Rails4: replace deprecated #connection from IssueQuery model

DEPRECATION WARNING: #connection is deprecated in favour of accessing it via the class.

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012717
Rails4: replace deprecated #connection from Repository model

DEPRECATION WARNING: #connection is deprecated in favour of accessing it via the class.

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012718
Rails4: replace deprecated #connection from Project model

DEPRECATION WARNING: #connection is deprecated in favour of accessing it via the class.

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012719
Rails4: replace deprecated #connection from Query model

DEPRECATION WARNING: #connection is deprecated in favour of accessing it via the class.

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012720
remove unneeded Relation#all from WorkflowsController

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012721
remove unneeded Relation#all from IssuePriority model

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012722
remove unneeded Relation#all from Mailer model

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012723
remove unneeded Relation#all from IssueQuery model

--HG--
extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012724