Add rustc wrapper as an option in cargo-casper

To properly use Verificator, Rust web-assembly builds must be deterministic, meaning the same binary is produced across different platforms and CPUs. Currently, cargo builds are not deterministic. To make the build reproducible on different platforms, build wrapper is required. Include in cargo-casper the use-wrapper option, which changes Makefile to make use of the wrapper, and compile and install the wrapper for the project.

casper-ecosystem / cargo-casper

Add rustc wrapper as an option in cargo-casper #69