A config file option is now available for all non-managed
parameters to CreateFunction. This data can also be passed
via build configuration if desired. Net net, we gain flexibility
and reduce the number of build options we add
This migrates from zig 0.13 to 0.15.2. In addition to dealing with
breaking changes in the build system and standard library APIs, the
architecture was changed substantially. We now build a standalone
CLI, and use that to execute the commands. This avoids sandboxing issues
related to TLS and enables easier testing. The commit also includes a
simple zip implementation (store only, single file) which avoids the
platform restriction (i.e. this build can now theoretically work on
Windows).
