Refactor compiler with singledispatch (#605)

Some small changes:

 * Refactor the Analyzer and Generator to use `functools.singledispatch` for some type based dispatch rather than a tree of `if isinstance(...)` branches.
 * Rename `List`, `Map`, `Set`, and `Vector` to `PersistentList`, `PersistentMap`, `PersistentSet`, and `PersistentVector` respectively.

Author: chrisrink10

CHANGELOG.md

@@ -22,6 +22,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
  * The compiler now uses the pre-computed hash to lookup keywords directly, which should improve lookup time for repeated invocations (#592)
  * Symbol hashes are now pre-computed when they are created (#592)
  * Moved `basilisp.core.template` to `basilisp.template` to match Clojure (#599)
+ * Refactor compiler to use `functools.singledispatch` for type based dispatch (#605)
+ * Rename `List`, `Map`, `Set`, and `Vector` to `PersistentList`, `PersistentMap`, `PersistentSet`, and `PersistentVector` respectively (#605)
 
 ### Fixed
  * Fixed a bug where `def` forms did not permit recursive references to the `def`'ed Vars (#578)

Makefile

@@ -44,7 +44,7 @@ pypy-shell:
 	@docker run -it \
 		--mount src=`pwd`,target=/usr/src/app,type=bind \
 		--workdir /usr/src/app \
-		pypy:3.6-7.0-slim-jessie \
+		pypy:3.6-7.3-slim-buster \
 		/bin/sh -c 'pip install -e . && basilisp repl'