Add rustc wrapper as an option in cargo-casper

[SaiProServ]

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.

[devendran-m]

Related PR is #68