Cellpy

* Switching from git-flow to github-flow
* New cli options for running batches
* cli option for creating template notebooks
* Using `ruamel.yaml` instead of `pyyaml`
* Using `python-box` > 4
* Several bug-fixes

* Starting fixing documentation
* TODO: create conda package
* TODO: extensive tests

* Refactoring - renaming from `dfsummary` to `summary`
* Refactoring - renaming from `step_table` to `steps`
* Refactoring - renaming from `dfdata` to `raw`
* Refactoring - renaming `cellpy.data` to `cellpy.get`
* Updated save and load cellpy files allowing for new naming
* Implemented cellpy new and cellpy serve cli functionality

* New batch-feature
* Improved make-steps and make-summary functionality
* Improved cmd-line interface for setup
* More helper functions and tools
* Experimental support for other instruments
* invoke tasks for developers

* Allow for using mdbtools also on win
* Slightly faster find_files using cache and `fnmatch`
* Bug fix: error in sorting files when using `pathlib` fixed

* Improved creation of step tables (much faster)
* Default compression on cellpy (hdf5) files
* Bug fixes