Shortest path implementation (#17)

* Implement the shortest path

* Add test script for shortest path

* Fix naming issue

* Update formatting

* Solve v1.6 compatability

* Update documentation

* Improve test coverage

* Fix document rendering

* Remove dependency on `DiGraph`

* Change test from random to known graph

* Update documentation

* Base shortest path on flow

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Co-authored-by: Guillaume Dalle <22795598+gdalle@users.noreply.github.com>

Author: adfeel220

.gitignore

@@ -3,6 +3,6 @@
 *.jl.mem
 /Manifest.toml
 /docs/build/
-/docs/Manifest.toml
+# /docs/Manifest.toml
 /docs/src/index.md
 .vscode/