Persistent Incremental Builds

[ErikMcClure]

inNative already has a form of incremental building but it only works in a single environment instance. Significant changes to how linking works are needed so that the necessary information can be persisted after destroying an environment (or closing the host process entirely). This essentially requires changing all globals to be declarations instead of aliases so that each LLVM module is entirely isolated in it's corresponding object file, allowing the linker to resolve the globals at link time, along with encoding enough metadata about the module so that we know when a recompilation is required.