Merge branch 'ty/migrate-excludes-file' into jch

The 'excludes_file' and various other global configuration variables (including 'editor_program', 'pager_program', 'askpass_program', and 'push_default') have been migrated into the per-repository structure. * ty/migrate-excludes-file: repository: adjust the comment of config_values_private_ environment: move object_creation_mode into repo_config_values environment: move autorebase into repo_config_values environment: move push_default into repo_config_values environment: migrate apply_default_whitespace and apply_default_ignorewhitespace environment: move askpass_program into repo_config_values environment: move pager_program into repo_config_values environment: move editor_program into repo_config_values environment: move excludes_file into repo_config_values repository: introduce repo_config_values_clear()