Add plain char* signatures WebServer::sendContent (#6341)
Add plain char* signatures WebServer::sendContent (#6341)

Fixes #2567

Allow the web server to send plain C strings instead of requring they be
encapsulated inside a String class object.  Saves memory vs. having to
convert C strings to Strings (i.e. duplication of data), overloads on
the efficient sendContent_P(char*) methods.
esp8266/Arduino,esp8266/Arduino,sticilface/Arduino,sticilface/Arduino,esp8266/Arduino,sticilface/Arduino,esp8266/Arduino,sticilface/Arduino,esp8266/Arduino,sticilface/Arduino