chore: add CHANGELOG template

Author: matmoncon

templates/CHANGELOG.md.j2

@@ -0,0 +1,24 @@
+# CHANGELOG
+{% if context.history.unreleased | length > 0 %}
+
+{# UNRELEASED #}
+## Unreleased
+{% for type_, commits in context.history.unreleased | dictsort %}
+{% if type_ in ["feature", "fix", "performance", "documentation", "refactor"] %}
+### {{ type_ | capitalize }}
+{% for commit in commits %}{% if type_ in ["feature", "fix", "performance", "documentation", "refactor"] %}
+* {{ commit.commit.message.rstrip() }} ([`{{ commit.commit.hexsha[:7] }}`]({{ commit.commit.hexsha | commit_hash_url }}))
+{% endif %}{% endfor %}{% endif %}{% endfor %}
+
+{% endif %}
+
+{# RELEASED #}
+{% for version, release in context.history.released.items() %}
+## What's Changed in {{ version.as_tag() }} ({{ release.tagged_date.strftime("%Y-%m-%d") }})
+{% for type_, commits in release["elements"] | dictsort %}
+{% if type_ in ["feature", "fix", "performance", "documentation", "refactor"] %}
+### {{ type_ | capitalize }}
+{% for commit in commits %}
+{% if type_ in ["feature", "fix", "performance", "documentation", "refactor"] %}
+* {{ commit.commit.message.rstrip() }} ([`{{ commit.commit.hexsha[:7] }}`]({{ commit.commit.hexsha | commit_hash_url }}))
+{% endif %}{% endfor %}{% endif %}{% endfor %}{% endfor %}