Issue - function sub-folders are not copied recursively

[alexellis]

Expected Behaviour

All / any assets such as a "src" or "samples" folder should be copied into the final image.

Current Behaviour

Only files in the root directory are copied in

Possible Solution

Seems as simple as setting a flag to "true" in the builder.

[alexellis]

@rgee0 https://github.com/alexellis/faas-cli/compare/recurse_function_copy?expand=1