added README.md

README.md

+README for OV-CAN-Node
+General purpose: direct CAN connection to an Attiny817
+
+Branches:
+	-Master: The MCP chips without Attiny817. Converts SPI to CAN. Possibly not complete.
+
+	-Attiny: SPI pins on Attiny817 QFN(24pin). Has output pins for 2 servos, 1 UART and 6 GPIO pins. Possibly not complete.
+
+	-Attiny_dobbel: Same as Attiny, but with both QFN(20pin) and SOIC(20pin). Complete version.