Merge branch 'ot/ref-filter-object-info'

A few atoms like %(objecttype) and %(objectsize) in the format specifier of "for-each-ref --format=<format>" can be filled without getting the full contents of the object, but just with the object header. These cases have been optimized by calling oid_object_info() API (instead of reading and inspecting the data). * ot/ref-filter-object-info: ref-filter: use oid_object_info() to get object ref-filter: merge get_obj and get_object ref-filter: initialize eaten variable ref-filter: fill empty fields with empty values ref-filter: add info_source to valid_atom