Temporarily get muggle files

Copies muggle files (get_muggle_file()) to the working directory. Files are deleted when .local_envir expires. If file already exists, only a warning is thrown. Useful to avoid pasting boilerplate files in muggle packages.

local_muggle_file(muggle_file, .local_envir = parent.frame())

Arguments

muggle_file	File to copy, relative path from built package root.
.local_envir	[environment] The environment to use for scoping.