chore: add changelog and release 0.2.0"

Closes #4 (closed)

CHANGELOG.md

+# Changelog
+
+All notable changes to this project will be documented in this file.
+
+## [0.2.0] - 2023-12-14
+
+### Features
+
+- Basic metric query selector/builder
+- Binary Operators with Vector Matching
+
+### Miscellaneous Tasks
+
+- Update README
+- Simple code example in README
+- Fix typo in README
+- Bump prometheus-http-query to 0.8.0
+- Bump version to v0.2.0
+- Include cliff.toml
+- Generate changelog for v0.2.0
+
+<!-- generated by git-cliff -->