setup multiple dendrometer on a single client, new setup with 2 dendrometer is on the desk of room 3N10

refactor f_deep_sleep.cpp into its own namespace, add boot counter, move to ESPLOG for wakeup reason

- messages are now built using the constructor
- messages now only contain a single measurement value, even if a sensor might include more than one measurement
- buildMessage has been changed to buildMessages and now returns a list of messages depending on how many measurements a sensor contains
- ClientDataPackage now builds from SensorInformation and MeasurementData
- minor naming refactors

fipy host broadcasts its mac + timestamp on start, main function of client updated according to last commit