Conversion to pydantic and various bugfixes/improvements

What's Changed

• Auto-reconnect to Stomp when connection lost by @callumforrester in #101
• Improve code coverage by @callumforrester in #102
• Use Correlation ID by @callumforrester in #103
• Switch from using apischema to pydantic by @callumforrester in #90
• Add comments to pydantic code by @callumforrester in #123
• Add repr of ScanSpec to Scan Plan metadata and add tests for #50 resolution by @DiamondJoseph in #125
• Add developer documentation by @callumforrester in #129
• Fix bullet points in docs by @callumforrester in #130

New Contributors

• @DiamondJoseph made their first contribution in #125

Full Changelog: 0.1.0...0.2.0