Geoh5py

A major release adding new classes and addressing issues with the DrillholeGroup class.

- Fixes for concatenated DrillHoleGroup
- GEOPY-598: Implement IntegratorDrillholeGroup class
- GEOPY-583: Better handling of adding and removing concatenaned drillholes and data intervals.
- GEOPY-584: Preserve integer values on IntegerData class.
- GEOPY-548: Allow TextData values on vertices and cells.
- GEOPY-329: API implementation of DrapeModel object class.
- GEOPY-462: Documentation fixes

This release addresses issues encountered after the 0.3.0 release.

- GEOPY-608: Check for 'allow_delete' status before removing.
- GEOPY-600: Fix crash on missing 'Group types' group from a project written by ANALYST.
- GEOPY-587: Increase PEP8 compliance after pylint update.
- GEOPY-575: Improve ui.json documentation.

What's Changed
* GEOPY-497: Implement SimPEG Group for storing inversion results
* GEOPY-314 - Update Drillhole entity for GA 4.0. Allow opening a Workspace as context manager.
* GEOPY-540: Allow opening workspace without a Root group
* GEOPY-539: Allow loading a workspace from bytes
* GEOPY-574: Make open return self. Augment unit test

Bug fixes
* GEOPY-511: do not always open geoH5 workspaces for writing from Python API
* GEOPY-514: Fix AtLeastOneValidation on natural source-inversion
* GEOPY-508, GEOPY-533: Refactor for read-only mode
* GEOPY-542: Root written without reference to children after creation
* GEOPY-543: Always import annotations from future
* GEOPY-568: Cannot select mesh from ui.json dropdown


**Full Changelog**: https://github.com/MiraGeoscience/geoh5py/compare/v0.2.0...v0.3.0

What's Changed
- Fix StatsCache on value changes.
- Fix crash if data values are None.
- Clean up for linters

- Add documentation for ui.json format.
- Fix for copying of direct-current survey.
- General documentation maintenance.