Use tinyvec

[JakubOnderka]

Utilising tinyvec::ArrayVec instead of Vec provides around 10 % better performance

[oschwald]

I'd like to limit the number of dependencies, particularly in the default install. Although I have having a hard time showing a noticeable performance difference between the three implementations with the included benchmarks, what about something like this instead?

[oschwald]

I am closing this in favor of #90.