docs/esp8266: In TCP tutorial, add HTTP response code and content-type.
docs/esp8266: In TCP tutorial, add HTTP response code and content-type.

Show how to send an HTTP response code and content-type.  Without the
response code Safari/iOS will fail.  Without the content-type Lynx/Links
will fail.

adafruit/circuitpython,tobbad/micropython,MrSurly/micropython,adafruit/circuitpython,kerneltask/micropython,bvernoux/micropython,adafruit/circuitpython,bvernoux/micropython,tobbad/micropython,pozetroninc/micropython,tobbad/micropython,henriknelson/micropython,pozetroninc/micropython,MrSurly/micropython,selste/micropython,pramasoul/micropython,pozetroninc/micropython,selste/micropython,pramasoul/micropython,bvernoux/micropython,pozetroninc/micropython,selste/micropython,MrSurly/micropython,kerneltask/micropython,henriknelson/micropython,kerneltask/micropython,tobbad/micropython,pramasoul/micropython,henriknelson/micropython,pramasoul/micropython,kerneltask/micropython,henriknelson/micropython,MrSurly/micropython,MrSurly/micropython,tobbad/micropython,henriknelson/micropython,adafruit/circuitpython,adafruit/circuitpython,pramasoul/micropython,selste/micropython,bvernoux/micropython,adafruit/circuitpython,kerneltask/micropython,bvernoux/micropython,pozetroninc/micropython,selste/micropython