Add CHANGELOG to the project

Add a CHANGELOG to keep track of changes in the project. This follows
the "keep a changelog" format [1], in same fashion as the rest of
rust-vmm crates.

[1] https://keepachangelog.com/en/1.1.0/

Signed-off-by: Babis Chalios <[email protected]>

Author: bchalios

CHANGELOG.md

@@ -0,0 +1,20 @@
+# Changelog
+
+## Upcoming version
+
+### Added
+### Changed
+### Fixed
+
+- [[#44]](https://github.com/rust-vmm/vm-allocator/pull/44): Fixed issue that
+  did not allow the creating of inclusive ranges of size 1.
+
+### Removed
+### Deprecated
+
+## [v0.1.0]
+
+### Added
+
+- Added types for (de)allocation of resources needed by the VMM during the VM
+  lifetime.