v1.5.0

• Support Click 7.0
• Remove unused __future__ imports
• #471 Update libtmux 0.8.0 -> 0.8.1
• Sort imports
• Add configuration and make command for isort.
• Add sphinxcontrib-napoleon.
• Assure requirements/dev.txt dependencies are in Pipfile
• Update sphinx, releases to latest version
• Sync requirements/*.txt dependencies with Pipfile.
• Update docstring style to use numpy-style documentation. This enhances readability and plays nicely with sphinx documentation.
• Documentation overhaul.
• Areas like :meth:tmuxp.cli.load_workspace are now documented verbosely. This is so contributors helping on the project can more quickly gain situational awareness in this tricky area of code.