build: specifying the feature flags in cargo optimize

[SebastianElvis]

we should keep a single name for the contracts. Whether you build the lite or full version is something you should take into consideration. Perhaps adding a Features column into the checksums.txt file.

This is not trivial as the optimiser provides support for specifying feature flags in CLI at the moment. It captures all build targets via parsing Cargo.toml here. This function extracts the standard build and all other builds. Then the code builds everything inside it.