Merge branch 'fc/fast-export-persistent-marks'

Optimization for fast-export by avoiding unnecessarily resolving arbitrary object name and parsing object when only presence and type information is necessary, etc. * fc/fast-export-persistent-marks: fast-{import,export}: use get_sha1_hex() to read from marks file fast-export: don't parse commits while reading marks file fast-export: do not parse non-commit objects while reading marks file