Tests if filename has a valid extension for an X.509 private key file
(".der", ".key", ".pem", or ".p12"), and contains a private key in a format
recognized by NetworkManager.
Parameters
filename: string
name of the file to test
Returns [boolean,boolean]
true if the file is a private key, false if it is not
Tests if
filenamehas a valid extension for an X.509 private key file (".der", ".key", ".pem", or ".p12"), and contains a private key in a format recognized by NetworkManager.