Refactor matricizer, fix some linter complaints

* Matricizer.choose_dimensions was not actually being used. It has been
  removed, and dimensions of the hash matrix are now determined
  internally by the matricizer, rather than in its constructor.
* Linter was complaining about missing documentation and some other
  minor styling things so those are fixed
* Linter had a few more stupid lints enabled ("too-many-statements"?
  really? god forbid your code is too long, I'm not a computer science
  student, come on guys)

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

.pylintrc

@@ -438,7 +438,9 @@ disable=raw-checker-failed,
         use-implicit-booleaness-not-comparison-to-zero,
         too-many-locals,
         too-few-public-methods,
-        line-too-long
+        too-many-statements,
+        line-too-long,
+        redefined-builtin,
 
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