v 5.1.0 is a bug fix release.
fixes #2685 "Clicking "Manage Members" in a vlan subinterface of a cluster causes crash".
fixed SF bug #3468358 "change in rule-compilation between 5.0.0 and 5.0.1". Rule with cluster interface in "Destination" should compile into matching ip addresses assigned to the cluster interface object and corresponding member firewall's interface object, but in v5.0.1 it only matched member interface address. This bug triggered when iptables version was set to 1.2.11 or greater. This was a regression from v5.0.0
fixes #2686 "automatic rules for heartbeat are not generated for vlan subinterfaces"
fixes #2684 "fix address deletion in configlet update_addresses". This only applies to Linux firewalls and configurations where an interface has two or more ip addresses. If user deleted one of the addresses that happens to be the "primary" address of the interface in the GUI, generated script deleted both addresses on the firewall machine instead of just one and left interface with no addresses at all. The fix is to use /proc variable /proc/sys/net/ipv4/conf/all/promote_secondaries that makes the kernel "promote" secondary address to a "primary" status when primary address is deleted. Default behavior in Linux kernel is to delete all addresses when primary address is deleted.
using mktemp to create temporary directory in the generated script. If mktemp is not available, fall back onto less secure but guaranteed to work method where I generate randomized the name of the temporary directory using process ID.
fixes SF bug 3489096 "dd-wrt-jffs: all routes are deleted if there is an error". The problem affects all supported Linux-like systems. Shell code that restores old static routing table entries in case of an error with commands adding new routing entries was broken and left the machine with no routes at all.
fix for SF bug #3468802. Need to define macro __STDC_FORMAT_MACROS. This still needs to be tested on all build machines.