ENH: Fix config for xorbits and xorbits.pandas

[luweizheng]

• add config options for xorbits
• add set_option() and get_option() for xorbits
• fix xorbits.pandas's bug when setting a non-existing option.
• update docs on configuration and chunking.

Check code requirements

• tests added / passed (if needed)
• Ensure all linting tests pass

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 82.98%. Comparing base (92fdfc5) to head (864ffc7).
Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #818   +/-   ##
=======================================
  Coverage   82.97%   82.98%           
=======================================
  Files        1070     1071    +1     
  Lines       80039    80083   +44     
  Branches    16531    16545   +14     
=======================================
+ Hits        66411    66455   +44     
+ Misses      12033    12022   -11     
- Partials     1595     1606   +11     

Flag	Coverage Δ
unittests	82.89% <ø> (+<0.01%)	⬆️

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[hucorz]

LGTM