Refactor repo.isBare to repo.isEmpty #5629 (#5714)

* Refactor repo.isBare to repo.isEmpty #5629

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Remove Sync call

models/migrations/migrations.go

@@ -208,6 +208,8 @@ var migrations = []Migration{
 	NewMigration("add pull request rebase with merge commit", addPullRequestRebaseWithMerge),
 	// v77 -> v78
 	NewMigration("add theme to users", addUserDefaultTheme),
+	// v78 -> v79
+	NewMigration("rename repo is_bare to repo is_empty", renameRepoIsBareToIsEmpty),
 }
 
 // Migrate database to current version