Release v0.6

Release vm-memory v0.6, with latest dirty track bitmap implementation.

Author: jiangliu

CHANGELOG.md

@@ -1,6 +1,8 @@
 # Changelog
 ## [Unreleased]
 
+## [v0.6.0]
+
 ### Added
 
   - [[#140]](https://github.com/rust-vmm/vm-memory/issues/140): Add dirty bitmap tracking abstractions. 

Cargo.toml

@@ -1,8 +1,9 @@
 [package]
 name = "vm-memory"
-version = "0.5.0"
+version = "0.6.0"
 description = "Safe abstractions for accessing the VM physical memory"
 keywords = ["memory"]
+categories = ["memory-management"]
 authors = ["Liu Jiang <gerry@linux.alibaba.com>"]
 repository = "https://github.com/rust-vmm/vm-memory"
 readme = "README.md"