Adds SSL server mode for WiFiServerSecure, for plain SSL connections,
ESP8266WebServerSecure, for HTTPS web serving, and SecureHTTPSUpdater for
encrypted OTA updates.
Example code is provided for all new options, as well as a BASH script for
generating their own, self-signed certificates.
Both ESP8266WebServerSecure and SecureHTTPSUpdater are important for secure
password-based authentication. HTTP Basic Authentication, the only supported
model presently, sends the username and password in *cleartext* and therefore
should *never* be used in any un-SSL encrypted channel unless you don't mind
sharing your login and password with anyone else on the internet. Even if the
ESP8266 is not safety critical, this cleartext broadcast could expose you should
you reuse this password elsewhere on your network or the internet.
