Client certificate from local storage

[akioyamamoto1977]

Added a feature to read a client certificate from local storage.

Connection with issue(s)

Resolve issue #1085

The original code supports only loading a client certificate in assets folder. This customization is to load from local storage tree if the certificate path begins with "/" (full path)

Testing and Review Notes

No screen shot, but only few lines added. Both localstorage and assets files are tested to be loaded as a client certificate