Use cameras other that PS3 Eye

[ju1ce]

This PR is not really ready to merge, it just contains some changes that I did to the repository to get my setup working a while back. As I have seen some people interested in this project, I decided to PR the changes on the chance it may help someone in the future.

• It allows you to use any USB webcam
• Added some code to flip image 90°, to make it easier to see the entire body

To use the feature, change the PS Eye camera to Other when adding a new camera, then select the ID the camera is on. This will usualy be 0,1,2 etc... To prevent the camera from being rotated, remove the cv2.rotate lines after the .read() lines.

TODO:

• Better enumeration of cameras. Selecting the camera by ID sucks, you dont know which camera will it open until you try, and windows may just decide to change the ID sometime after which the program will crash on startup (since camera cannot be opened)
• fix visualization to work properly on different aspect ratios
• Probably other things. Its been a while since I last tried it...

[noahcoolboy]

Hello!
I has tried to ask you a few questions on discord about this pull request, but with no luck. So I'll just ask here:

1. How was your experience with toucan track?
2. Why lower the default fps from 50 to 30? This may cause lighting issues for most cameras due to the flashing of LED bulbs
3. Doesn't the rotation of the camera cause issues with the tracking? The detection model might not be used to that orientation.

Thank you for your contribution!