Add machine week page

content/12_machine_week.md

static/designs/12_temp_control.brd

static/designs/12_temp_control.sch

static/designs/12_temp_control_cutout.png

static/designs/12_temp_control_routes.png

static/img/12_adc_test.png

static/img/12_chocolate_syringe.jpg

static/img/12_disco_cad.mp4

static/img/12_extruder.jpg

static/img/12_network_test.png

static/img/12_temp_board.jpg

static/img/12_temp_control.mp4

static/reference/12_NTC-3950-100K.pdf