4.4.0

• Update year and update license test to 2020.
• Bump OSVVM to latest version.
• Add possibility to configure random stalls for AXI Stream. (#557)
• JSON-for-VHDL: use base16 encodings. (#595)
• First release requiring Python 3.6 or higher. Python 2.7, 3.4 and 3.5 are not supported anymore. (#596, #601)
• Start adding type annotations to the Python sources; add mypy (a static type checker) to the list of linters. (#601, #626)
• Move co-simulation (VHPIDIRECT) sources (implementation and example) to VUnit/cosim. (#606)
• ghdl interface: with ghdl_e, save runtime args to JSON file. (#606)
• Add missing mode assertions to -93 sources of integer_vector_ptr and string_ptr. (#607)
• Add method get_simulator_name() to public Python API. (#610)
• Start replacing join, dirname, etc. with pathlib. (#612, #626, #632)
• Fix parsing adjacent hyphens in a literal. (#616)
• Fix ghdl.flags error in documentation. (#620)
• Rename compile option ghdl.flags to ghdl.a_flags. (#624)
• Move project.Library to separate file.
• Remove Travis CI and AppVeyor, use GitHub Actions only.
• Remove Sphinx extension ABlog; handle posts as regular pages in subdir blog.
• Update GHDL to v0.37 in Windows CI jobs.
• Fix regression in GHDL (prefix of array attribute must be an object name). (#631, #635)
• Add code coverage support for GHDL. (#627)