Preload issue relations when exporting issues to CSV with all columns (#16091).

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012910
Preload issue authors when displayed on the issue list (#16091).

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012911
Preload authors for /issues API calls.

--HG--
extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012912
Prevent N queries on custom_fields when call /issues API.

--HG--
extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012913
Only notify users that can see news (#16134).

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012914
Trigger basic HTTP authentication only when Basic authorization header is present (#16107).

--HG--
extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012915
Strip invalid UTF-8 bytes in User#find_by_login (#16107).

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extra : convert_revision : svn%3Ae93f8b46-1217-0410-a6f0-8f06a7374b81/trunk%4012916