Better error messages for unknown initialization keyword arguments

[Midnighter]

• fix Make error message more intuitive if you get a wrong parameter on an element constructor #50
• description of feature/fix
• tests added/passed
• add an entry to the next release

I couldn't push to your branch (PR #51 addressing #50) so I've made a new branch. This pushes the keyword argument handling down to AbstractBase where multiple inheritance should never be an issue. Let me know what you think about this approach @yt-ms

[codecov-io]

Codecov Report

Merging #60 (0c5069d) into devel (ba22ca8) will increase coverage by 0.03%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##            devel      #60      +/-   ##
==========================================
+ Coverage   90.11%   90.14%   +0.03%     
==========================================
  Files          68       68              
  Lines        1953     1959       +6     
  Branches      171      173       +2     
==========================================
+ Hits         1760     1766       +6     
  Misses        173      173              
  Partials       20       20              

Impacted Files	Coverage Δ
src/structurizr/abstract_base.py	92.85% <100.00%> (+5.35%)	⬆️

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[yt-ms]

Looks good. One small suggestion to simplify.