Add repository setting to enable/disable health checks (#3607)

New Feature:
  * Repository struct field for IsFsckEnabled (default true of course)
  * Admin Settings section on repo options page, accessible only by
    admin users

Possible Enhancements:
  * There's no way to force running health checks on all repos
    regardless of their IsFsckEnabled setting. This would be useful if
    there were an admin API or dashboard button to run fsck immediately.

Issue: https://github.com/go-gitea/gitea/issues/1712
Signed-off-by: Allen Wild <allenwild93@gmail.com>

modules/auth/repo_form.go

@@ -113,6 +113,9 @@ type RepoSettingForm struct {
 	PullsAllowSquash                 bool
 	EnableTimetracker                bool
 	AllowOnlyContributorsToTrackTime bool
+
+	// Admin settings
+	EnableHealthCheck bool
 }
 
 // Validate validates the fields