Added stats generation

[brwarner]

Checklist

• The new code additions passed the tests (npm test).
• The linter ran and found no issues (npm run-script lint).
• Check the ink repository for any tests to migrate surrounding stats

Description

Adding stats generation from the ink compiler to inkjs. The ink compiler only exposes this as a command line option, but for inkjs I've exposed it as a new function in the Compiler that can be run after compilation.

For source from the ink repository, see https://github.com/inkle/ink/blob/master/compiler/Stats.cs

[brwarner]

There are no tests in the ink repository around story stats

[smwhr]

Thanks for porting this stat counter !

Although adding one simple test case for the function to insure no one breaks it unintentionally in the future would be a nice addition, don't you think ?

[brwarner]

For sure, I'll add one in!

[brwarner]

Tests are in src/tests/specs/inkjs/compiler/Stats.spec.ts

[smwhr]

Merged ! 🚀

[smwhr]

The number of diverts is not counted in the same manner as when called with the original inklecate.

Ex, on the file src/tests/inkfiles/original/inkjs/tests.ink

• this implementations reports 101 diverts
• the inklecate implementation reports 131 diverts

This has nothing to do with your code, so I will just open a new issue for later resolution.
Also, who is really interested in the number of diverts ?