There are several unresolved -Wmissing-field-initializers on older versions of GCC than 5.1, all of them false positive.
Since 2.6.19, the netlink API defines RTA_TABLE routing attribute to allow 32-bit routing table IDs. Using this attribute to index routing tables at Linux, instead of 8-bit rtm_table field.
Linux kernel route metrics (RTA_METRICS netlink route attribute) are represented and accessible as new route attributes: krt_mtu, krt_window, krt_rtt, krt_rttvar, krt_sstresh, krt_cwnd, krt_advmss, krt_reordering, krt_hoplimit, krt_initcwnd, krt_rto_min, krt_initrwnd, krt_quickack, krt_lock_mtu, krt_lock_window, krt_lock_rtt, krt_lock_rttvar, krt_lock_sstresh, krt_lock_cwnd, krt_lock_advmss, krt_lock_reordering, krt_lock_hoplimit, krt_lock_rto_min, krt_feature_ecn, krt_feature_allfrag
Inspired by the patch from Alexander V. Chernikov.
Adding some files that was accidentally removed (instead of moved) in cleanup part 2.
