Adds fading between windows in Swaywm.

1. Download the swayfader.py file.
2. Install python3 and python-pip packages through pacman.
3. Install the i3ipc module: sudo python3 -m pip install i3ipc
4. add exec python3 /path/to/swayfader.py to your sway config to have the program launch at startup. Alternatively, run python3 /path/to/swayfader.py to start the program manually.

The opacities and fade durations can be configured through environment variables. For example, SWAYFADER_CON_INAC for inactive window opacity. When not set, the values have sane defaults.

CON refers to a normal tiled window, while BOT refers to a tiled window that has just lost focus to a floating window. Everything else should be self-explanatory.