[Documentation] Rework for v0.2.2

[skim0119]

Documentation Update

Here is the sample build of the updated documentation pages. There might be a few updates/fixes that are necessary, but I think we can continue working on those in branch update-0.2.2.

https://docs.cosseratrods.org/en/doc_patch/index.html

Key Changes

• The workflow and tutorial in the webpage are merged in the documentation page.
• Each module is listed in the table.
• Compatibility table is added to indicate which modules are supported in rigid body vs rod.
• Advanced guide is added to archive important discussions.
• Old information is removed, new information are added 😄

[codecov-commenter]

Codecov Report

Merging #65 (e7df9a8) into update-0.2.2 (71bebe1) will increase coverage by 0.03%.
The diff coverage is 100.00%.

@@               Coverage Diff                @@
##           update-0.2.2      #65      +/-   ##
================================================
+ Coverage         86.41%   86.44%   +0.03%     
================================================
  Files                38       39       +1     
  Lines              2606     2612       +6     
  Branches            370      370              
================================================
+ Hits               2252     2258       +6     
  Misses              326      326              
  Partials             28       28              

Impacted Files	Coverage Δ
elastica/_calculus.py	95.87% <ø> (ø)
elastica/callback_functions.py	79.74% <ø> (ø)
elastica/external_forces.py	95.65% <ø> (ø)
elastica/joint.py	25.17% <ø> (ø)
elastica/utils.py	98.18% <ø> (ø)
elastica/boundary_conditions.py	95.36% <100.00%> (ø)
elastica/rigidbody/cylinder.py	100.00% <100.00%> (ø)
elastica/rigidbody/rigid_body.py	54.54% <100.00%> (ø)
elastica/rigidbody/sphere.py	100.00% <100.00%> (ø)
elastica/rod/__init__.py	100.00% <100.00%> (ø)
... and 3 more

---

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[armantekinalp]

After the changes we can merge this documentation. LGTM

[armantekinalp]

I also reformatted some documentation @skim0119