Deprecation

sz: Support S2 (close #429) (#431)

go.mod: Upgrade sevenzip

fs: Don't make implicit entries for actual files (fix #430)

zip: Update szip append

Upgrade rar lib

oops; update readme for beta.9 changes

Refactor and simplify interfaces

Reuse code to determine stream size by seeking

Refactor FS types; improve performance (#426)

build: upgrade rardecode to v2.0.0-beta.3 (#423)

chore(go.mod): Switch to upstream lzip package (#422)

go.mod: Use copy of lzip library that disappeared (close #421)

zip: Fix compression method not set without SelectiveCompression enabled (#419)

fs: Fix bug with ArchiveFS stat method