Move the CHANGELOG to a Markdown file
Convert CHANGELOG to Markdown syntax
Add a release data for version 0.1.0

This is when acts_as_geocodable was still a plugin rather than a proper
gem.
Fill in the CHANGELOG blanks
Categorize CHANGELOG entries

…according to https://github.com/tech-angels/vandamme.
Document the unreleased version 2.1.0 in the CHANGELOG
Target version 2.1.0
Merge pull request #33 from collectiveidea/changelog

Give the CHANGELOG some much needed love