WIP: Modernizing setup.

Summary

Replacing long deprecated tests_requires by a test extra.

Focus

Does the pipeline pass?

Test Environment

Pipeline.

Check List for the Author

Please, prepare your MR for a review. Be sure to write a summary and a focus and create gitlab comments for the reviewer. They should guide the reviewer through the changes, explain your changes and also point out open questions. For further good practices have a look at our review guidelines

• All automated tests pass
• Reference related issues
• Up-to-date CHANGELOG.md (or not necessary)
• Up-to-date JSON schema (or not necessary)
• Appropriate user and developer documentation (or not necessary)
  • How do I use the software? Assume "stupid" users.
  • How do I develop or debug the software? Assume novice developers.
• Annotations in code (Gitlab comments)
  • Intent of new code
  • Problems with old code
  • Why this implementation?

Check List for the Reviewer

• I understand the intent of this MR
• All automated tests pass
• Up-to-date CHANGELOG.md (or not necessary)
• Appropriate user and developer documentation (or not necessary)
• The test environment setup works and the intended behavior is reproducible in the test environment
• In-code documentation and comments are up-to-date.
• Check: Are there specifications? Are they satisfied?

For further good practices have a look at our review guidelines.

README_SETUP.md

@@ -2,19 +2,6 @@
 
 ## Installation ##
 
-### Requirements ###
-
-PyCaosDB needs at least Python 3.8.  Additionally, the following packages are required (they will
-typically be installed automatically):
-
-- `lxml`
-- `PyYaml`
-- `PySocks`
-
-Optional packages:
-- `keyring`
-- `jsonschema`
-
 ### How to install ###
 
 #### Linux ####
@@ -73,12 +60,25 @@ cd caosdb-pylib
 pip3 install --user .
 ```
 
-For installation of optional packages, install with an additional option, e.g. for 
-validating with the caosdb json schema:
+#### Additional dependencies ####
+
+To test using tox, you also need to install tox:  
+`pip3 install tox --user`  
+
+To install dependencies used by optional functionality, the following pip extras 
+keywords are defined:
+- `test` for testing with pytest
+- `mypy` for mypy and types
+- `jsonschema` 
+- `keyring` 
 
+These extras can be installed using: 
 ```sh
-pip3 install --user .[jsonschema]
+pip3 install --user .[KEYWORD]
 ```
+A current list of the dependencies installed with this program as well as those installed with 
+the keywords can be found in `setup.py`s `setup_package()` method, in the `metadata` dictionary
+entries `install_requires` and `extras_require`.
 
 ## Configuration ##
 
@@ -87,7 +87,7 @@ is described in detail in the [configuration section of the documentation](https
 
 ## Try it out ##
 
-Start Python and check whether the you can access the database. (You will be asked for the
+Start Python and check whether you can access the database. (You will be asked for the
 password):
 
 ```python
@@ -107,6 +107,7 @@ Now would be a good time to continue with the [tutorials](tutorials/index).
 - Run all tests: `tox` or `make unittest`
 - Run a specific test file: e.g. `tox -- unittests/test_schema.py`
 - Run a specific test function: e.g. `tox -- unittests/test_schema.py::test_config_files`
+- To run using pytest: `pytest .`
 
 ## Documentation ##
 We use sphinx to create the documentation. Docstrings in the code should comply