update to installation documentation

[kylethieringer]

Hello,

After having some trouble with downloading deepethogram I wanted to offer my advice on how I was successful in getting the gui to run on my system: OS: Ubuntu 22.04 GPU: RTX 2080 Cuda: 11.6

Conda environments consistently failed, running into issues listed in the troubleshooting section, however the suggested fixes did not work for me. I coninually ran into dependency issues with conda install / pip install within conda so I moved to creating a python virtual environment.

$ python3 -m venv /home/kyle/deg
$ source /home/kyle/deg/bin/activate
$ pip3 install torch torchvision torchaudio --extra-index-url https://download.pytorch.org/whl/cu116
$ pip3 install deepethogram

pip installing deepethogram installs pySide2, cv2-headless, etc already so the "brief" installation section can actually be briefer haha.

this virtual env installation worked very smoothly. Im excited to now start playing around with some videos :)