Added discrete_sreries example tutorial

[Robert-Jia00129]

Added quickstart tutorial for Python. Created a quickstart notebook that help new users quickly learn basic concepts and implementation in ~10 minutes.

Major topics:

• how gtsam variables are represented
• how to create variables
• how to print/display variable
• how to use FactorGraphs
• conditional probabilities
• sampling and assigning variables

Need helps -- TODO:

• I'm not sure how to add this to the docs pages at https://borglab.github.io/gtsam/
• Upload to colab (but probably not under my name)

[dellaert]

Nice, Robert!

• I'd not market it as a python tutorial for gtsam, per se, but as an example.
• I'd put this in the python/gtsam/examples folder, along with other examples, and call it DiscreteMotionModel.ipynb or something. It will automatically appear.
• You probably want to refer people to the online book, as that's where it's coming from
• Finally, look at 6 More Python Examples + Standardized Notebook Format #2288 - it has a handy script to add the "standard" cells at the beginning of an example. That will also install the "open in colab" button

[Robert-Jia00129]

• I'd not market it as a python tutorial for gtsam, per se, but as an example.

• I'd put this in the python/gtsam/examples folder, along with other examples, and call it DiscreteMotionModel.ipynb or something. It will automatically appear.

• You probably want to refer people to the online book, as that's where it's coming from

• Yes. I referred to it in the guide in several places. I'll refer to it in the very beginning as well.

• Finally, look at 6 More Python Examples + Standardized Notebook Format #2288 - it has a handy script to add the "standard" cells at the beginning of an example. That will also install the "open in colab" button

• I saw the Python script. We should probably also bring it into develop branch.

[Robert-Jia00129]

@dellaert Just updated the image path. It should be good now. I'll try putting everything in the examples folder so we don't waste the extra resources :)

[dellaert]

Oops, CI fails on Mac. Brew issue. Not your fault but if you can fix it great :-)

[dellaert]

@Robert-Jia00129 do you have a mac? Is it easy to check a fix?

[Robert-Jia00129]

@Robert-Jia00129 do you have a mac? Is it easy to check a fix?

Still looking into this. Haven't pinpointed what's causing the issue yet.