docs: document all command line arguments

[olavloite]

Adds a separate documentation page for all command line arguments and cleans up the main README file a little.

[codecov]

Codecov Report

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@@                  Coverage Diff                  @@
##             postgresql-dialect     #296   +/-   ##
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  Coverage                      ?   82.93%           
  Complexity                    ?     1331           
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  Files                         ?      109           
  Lines                         ?     4595           
  Branches                      ?      575           
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  Hits                          ?     3811           
  Misses                        ?      596           
  Partials                      ?      188           

Flag	Coverage Δ
all_tests	82.93% <0.00%> (?)

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