[system] update units to new configuration (closes #13)

config/pyheatpump_fetch.service

 [Unit]
 Description=pyHeatpump fetch - retrieve the data from the serial port with modbus
-Requires=serial-getty@ttyUSB0
+Wants=dev-ttyUSB0.device
 
 [Service]
 Type=simple
 WorkingDirectory=/var/lib/pyheatpump/
 Environment="LOGLEVEL=INFO"
-ExecStart=/usr/bin/env pyheatpump fetch
+ExecStart=/usr/bin/env pyheatpump fetch -t D -t A -t I
+ExecStop=/usr/bin/env pyheatpump supervise --since
 KillMode=mixed
 TimeoutStopSec=30
 PrivateTmp=true

config/pyheatpump_fetch.timer

 Description=Timer to launch pyheatpump fetch every minute
 
 [Timer]
-OnCalendar=*-*-* *:*:00
+OnStartSec=15sec
+OnUnitInactiveSec=1m
 
 [Install]
 WantedBy=timers.target

config/pyheatpump_supervise.service

-[Unit]
-Description=pyHeatpump supervise - communicates with the supervisor
-After=network.target
-
-[Service]
-Type=simple
-WorkingDirectory=/var/lib/pyheatpump/
-Environment="LOGLEVEL=INFO"
-ExecStart=/usr/bin/env pyheatpump supervise --since
-KillMode=mixed
-TimeoutStopSec=30
-PrivateTmp=true

config/pyheatpump_supervise.timer

-[Unit]
-Description=Timer to launch pyheatpump supervise every minute, with an offset of 30 seconds
-
-[Timer]
-OnBooSec=90s
-OnActiveSec=1m
-
-[Install]
-WantedBy=timers.target