Switch to maintained version of mmap

Author: jyn514

Cargo.lock

@@ -77,7 +77,7 @@ rusoto_credential = "0.46.0"
 # Data serialization and deserialization
 serde = { version = "1.0", features = ["derive"] }
 serde_json = "1.0"
-memmap = "0.7.0"
+memmap2 = "0.5.0"
 
 # iron dependencies
 iron = "0.6"

Cargo.toml

@@ -1,7 +1,7 @@
 use crate::error::Result;
 use crate::storage::{compression::CompressionAlgorithm, FileRange};
 use anyhow::{bail, Context as _};
-use memmap::MmapOptions;
+use memmap2::MmapOptions;
 use serde::de::DeserializeSeed;
 use serde::de::{IgnoredAny, MapAccess, Visitor};
 use serde::{Deserialize, Deserializer, Serialize};