MakeVariableMap is a convenience function to conert a `VariableSlice` to a `VariableMap`.

Run is responsible for assembling an interpreter's execution environment (setting environment variables, working directory, IO/output, etc) and running the command Accepts: - context - ULID specific to this run - path to the script - string containing the contents of the templated script - a slice of strings in `key=value` pair containing the merged variables to be provided to the script as environment variables.

SourceFile sources a shell file from disk and returns the variables declared in it.

SourceNode sources a shell program from a node and returns the variables declared in it.

VariableMap is an alias for `map[string]string`, where the key is the variable name and the string is the variable value.

VariableSlice is an alias for `[]string`, where each item is an environment variable in `key=value` form, the same as returned by `os.Environ()`.