Loads api keys from a file. File has to be one key per line, blank lines for formatting are allowed. Optionally, a comma separated list of scopes after the key and a colon in between the two. Hash symbol can be used for comments at the end of each line, including empty lines.

Example:

See: https://github.com/membrane/api-gateway/blob/master/distribution/examples/security/api-key/simple/demo-keys.txt