Add Canon Lens management

F1:F103/USB_Canon_management/Readme

@@ -0,0 +1,24 @@
+Canon lens management.
+
+Protocol have a string form, each string ends with '\n'. You should wait an answer for previous command before sending next,
+or have risk to miss all the rest commands in one packet.
+
+USB commands:
+
+0 - move to smallest foc value (e.g. 2.5m)
+1 - move to largest foc value (e.g. infinity)
+d - open/close diaphragm by 1 step (+/-), open/close fully (o/c) (no way to know it current status)
+f - get focus state or move it to given relative position
+h - turn on hand focus management
+i - get lens information
+l - get lens model
+r - get regulators' state
+                debugging commands:
+F - change SPI flags (F f val), f== l-LSBFIRST, b-BR [18MHz/2^(b+1)], p-CPOL, h-CPHA
+G - get SPI status
+I - reinit SPI
+R - software reset
+S - send data over SPI
+T - show Tms value
+
+