Added README and manual

README.md

+# watlow-f4t
+Modbus-TCP driver for Watlow F4T/D4T universal process controllers written in rust.
+
+## TODO
+### Implementation
+- [ ] Device Details
+- [x] Display
+- [ ] Alarm
+- [x] Control Loop
+- [ ] Cascade Loop
+- [ ] Compare
+- [ ] Counter
+- [ ] Current Input
+- [ ] Ethernet/Modbus
+- [ ] Key
+- [ ] Logic
+- [ ] Limit
+- [ ] Linearization
+- [ ] Math
+- [ ] Modbus RTU
+- [ ] Process Value
+- [x] Real Time Clock
+- [ ] Special Output Function
+- [ ] Timer
+- [x] Variable
+- [ ] Profile Engine
+- [ ] Profile Editor, Common
+- [ ] Profile Editor, 50 Steps
+- [x] Universal Input
+- [ ] Thermistor Input
+- [ ] Temperature Input
+- [ ] Analog Output
+- [ ] Discrete Input
+- [ ] Discrete Input/Output
+- [ ] Discrete Output *SSR & Switched DC/Open Collector*
+- [ ] Discrete Output, Limit
+- [ ] Discrete Output, Electromechanical Relay
+- [ ] Message List
+- [ ] Logging