raspberrypi-ua-netinst v2.1.0

Changelog:

• moved cpufrequtils from base to minimal preset
• added or changed configuration variables
  • set root partition label
  • set installation retries
  • set network timeout
  • set package update retries
  • set package download retries
  • removed ip_broadcast will be calculated from ip_addr and ip_netmask
• improved memory usage
• fix compatibility with 1B models with only 256 MB memory (revision 0002)
• detect and assign missing ip_netmask if ip_addr is in a private subnet

Bugfixes:

• fix RTC support
• fix custom wpa_supplicant.conf