Loop over the config files to load the static assets and mixin to the file struct pointer (e.g. - panos_tfid data source)

[pimielowski]

The current CodeGen mechanism can't work with different config files and structures other like *.spec file, because the purpose of the spec file was to contain normalized data, and based on it, it will generate SDK and Terraform Provider resources/datasources.
The issue is we need to tackle creating files with statically created code, but also we need to generate part of it AND include some information ie. in Provider.go (which will be generated).

This is a part of #61 requirement.