Packaging of crystal for T2215
Some notes about decisions made that may or may not be correct:
- Crystal is self-hosted by cross-compilation, so the first submission to the build service will be bootstrapped by a pre-built compiler. This can probably be removed later;
- Some flags generated by llvm-config --cxxflags are not recognised by g++, so these are removed (as mentioned earlier;
- --no-debug flag is passed to the compiler for the initial build due to an issue in one of the LLVMs (pre-built binary or Solus');
- Symbolic links are used in library files due to Solus' unique target triple (x86_64-solus-linux rather than x86_64-linux-gnu);
- Some tests in the check phase are skipped due to network dependencies, PATH checking, or not working in most reports I see;
- Many many documentation files, so I've used cp -a.