[#225] container: Replace basic ACL code to a separate package

Create `acl` package inside `container` path. Replace basic ACL
functionality into it.

Signed-off-by: Leonard Lyubich <leonard@nspcc.ru>

container/acl/init.go

@@ -0,0 +1,30 @@
+package acl
+
+func init() {
+	// left-to-right order of the object operations
+	orderedOps := [...]Op{
+		OpObjectGet,
+		OpObjectHead,
+		OpObjectPut,
+		OpObjectDelete,
+		OpObjectSearch,
+		OpObjectRange,
+		OpObjectHash,
+	}
+
+	mOrder = make(map[Op]uint8, len(orderedOps))
+
+	for i := range orderedOps {
+		mOrder[orderedOps[i]] = uint8(i)
+	}
+
+	// numbers are taken from NeoFS Specification
+	Private.FromBits(0x1C8C8CCC)
+	PrivateExtended.FromBits(0x0C8C8CCC)
+	PublicRO.FromBits(0x1FBF8CFF)
+	PublicROExtended.FromBits(0x0FBF8CFF)
+	PublicRW.FromBits(0x1FBFBFFF)
+	PublicRWExtended.FromBits(0x0FBFBFFF)
+	PublicAppend.FromBits(0x1FBF9FFF)
+	PublicAppendExtended.FromBits(0x0FBF9FFF)
+}