5.0.0

❤️ contributors: @hugovk, @foone, @SergeyKalutsky

• ⚠️ removed support for Python 2.7
• MSS: improve type annotations and add CI check
• MSS: use __slots__ for better performances
• MSS: better handle resources to prevent leaks
• MSS: improve monitors finding
• Windows: use our own instances of GDI32 and User32 DLLs
• doc: add project_urls to setup.cfg
• doc: add an example using the multiprocessing module (closes #82)
• tests: added regression tests for #128 and #135
• tests: move tests files into the package