Add probabilistic line extraction

[tn3wman]

I see circle fitting and rectangle fitting. It would be helpful to include probabilistic line extraction to detect walls in indoor environments. There are several implementations written in MATLAB here: https://github.com/acschaefer/ple

[AtsushiSakai]

PR is welcome. But note that the OSS’s license is GPL3.0, so we convert the code to Python is not acceptable. The code should be based on the original paper.

[AtsushiSakai]

Paper link: https://github.com/acschaefer/ple/blob/master/doc/ple_iros2018.pdf

[tn3wman]

Sounds good. I wasn't intending to convert the code from their research to Python, it's just the best example I have found with some implementations of more common algorithms such as iterative end point fit and split and merge. Hopefully it'll help troubleshoot issues with my own implementations, and if I get something working I'll create a PR.

[jpcoffelt]

I'd be interested in developing a Python solution from the source paper. Can this be assigned to me?

[AtsushiSakai]

Hi. Thank you for your interest. @jpcoffelt
Your PR is welcome. No need assignment.