Fix bug discovered by jonald, where a Python 3.6 feature (json bytes loading) was used, which was not supported in Python 3.5 and caused errors in plugin loading.
Fix bug discovered by jonald, where a Python 3.6 feature (json bytes loading) was used, which was not supported in Python 3.5 and caused errors in plugin loading.

fyookball/electrum,fyookball/electrum,fyookball/electrum