* Adds wax.os.setenv()
* Adds wax.lazy() - for modules with lazy loadable functions
* Project tree changed to accomodate C sources and Lua
  files under the same directory
* Adds support for C functions as submodules inside project
* Changed the module configuration file format (etc/config.lua)
* Adds SPDX tag across the project
* Docs for wax C helper headers