version 1.3.0

Python 3.6 and pytest 5.4.0.0 are now minimum requirements for pytest-workflow.
This was necessary for fixing the deprecation warning issue and the issue with
the subdirectory evaluation. This also gave the opportunity to simplify the
source code using new python 3.6 syntax.

• Using the name keyword argument in workflow marks will be deprecated
  from 1.4.0 onwards. A warning will be given if this is used. For example:
  pytest.mark.workflow(name="my_workflow"). Use the name as argument
  instead: pytest.mark.workflow("my_workflow").
• Allow running custom tests on multiple workflows. You can now use
  pytest.mark.workflow("worflow name 1", "workflow name 2", ...).
  (Issue #75 <https://github.com/LUMC/pytest-workflow/issues/75>_)
• Add a miniwdl example to the documentation.
• Added a --symlink flag to the CLI that changes the copying behavior.
  Instead of copying, it creates a similar directory structure where all files
  are linked to with symbolic links. (Issue #96 <https://github.com/LUMC/pytest-workflow/issues/98>_)
• Refactored the code base. Python 3.6's f-strings and type annotation were
  used consistently throughout the project. Some code was rewritten to be more
  concise and readable.
• Improved speed for searching string content in files. This was achieved by
  removing intermediate functions and simplifying the search function.
• Improved speed for calculating md5sums by increasing the read buffer size
  from 8k to 64k.
• Solve issue where pytest would display a lot of deprecation warnings when
  running pytest-workflow. (Issue #98 <https://github.com/LUMC/pytest-workflow/issues/98>_)
• Fix issues with later versions of Cromwell and Snakemake in CI testing.
• Add correct subdirectory evaluation to fix issue where /parent-dir/child
  was evaluated as a subdirectory of /parent due to starting with the same
  string. (Issue #95 <https://github.com/LUMC/pytest-workflow/issues/95>_)
• Fix error in cromwell example which did not allow it to remove folders
  correctly.