Scala Performance Style Guide

Here is a description of simple Scala tricks behind
upcoming 3-4x speedup of ErgoScript contracts validation.

Many more optimisations has been done in the upcoming release (see related PR for details),
but these guidelines are kind of “low hanging fruits” to boost the performance of Scala
code almost for free and are widely applicable.

If you are practicing Scala let us know your experience, contributions are very welcome.