refactor: xmltodict is only test dependency

[vinitkumar]

• Cleanup Readme
• Remove xmltodict as a dep from codebase, we only need it as a test dependency.
• Make the list of contributors correct.

[codecov-commenter]

Codecov Report

Merging #124 (6ab35e1) into master (6aafca8) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #124   +/-   ##
=======================================
  Coverage   89.11%   89.11%           
=======================================
  Files           5        5           
  Lines         441      441           
=======================================
  Hits          393      393           
  Misses         48       48           

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