Improve nested graph support

[rlouf]

OpFromGraph

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1. Support updates via the OpFromGraph interface #1316
   Op implementation enhancement +2
2. Merge Composite and OpFromGraph #1287
   Op implementation enhancement help wanted refactor +4
3. Reduce aesara.compile.builders.infer_shape's recursions #1117
   Scan bug help wanted performance concern shape inference +5

Scan

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1. Use Scan input storage more efficiently #1230
   Scan enhancement help wanted performance concern refactor +5
2. Reduce aesara.compile.builders.infer_shape's recursions #1117
   Scan bug help wanted performance concern shape inference +5
3. Merge Scan's inner-graphs without graph traversal #777
   Scan enhancement help wanted important performance concern refactor +6
4. Scan refactoring and simplification #584
   Scan enhancement help wanted refactor +4
5. Add Scan rewrites to canonicalizations #580
   Scan enhancement graph rewriting help wanted +4
6. In-place the RandomVariables within a Scan #543
   Scan enhancement graph rewriting help wanted random variables +5
7. Behaviour of scan differs from documentation wrt variables with no taps #500
   Scan bug documentation enhancement good first issue help wanted +6
8. Support RandomState Variable types in Scan #738
   Scan enhancement help wanted important random variables refactor request discussion +7