Doc: Add documentation for OSPF retransmit delay option

Thanks to Igor Podlesny for notification.
32 jobs for master in 5 minutes and 22 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Image
passed #225347
dind allowed to fail
docker_centos-6-amd64

00:00:34

passed #225348
dind allowed to fail
docker_centos-7-amd64

00:00:34

passed #225337
dind allowed to fail
docker_debian-7-amd64

00:00:31

passed #225341
dind allowed to fail
docker_debian-7-i386

00:00:32

passed #225338
dind allowed to fail
docker_debian-8-amd64

00:00:30

passed #225342
dind allowed to fail
docker_debian-8-i386

00:00:31

passed #225339
dind allowed to fail
docker_debian-9-amd64

00:00:30

passed #225343
dind allowed to fail
docker_debian-9-i386

00:00:31

passed #225340
dind allowed to fail
docker_debian-testing-amd64

00:00:32

passed #225344
dind allowed to fail
docker_debian-testing-i386

00:00:30

passed #225345
dind allowed to fail
docker_fedora-25-amd64

00:00:32

passed #225346
dind allowed to fail
docker_fedora-26-amd64

00:00:31

passed #225349
dind allowed to fail
docker_opensuse-42_3-amd64

00:00:35

passed #225350
dind allowed to fail
docker_ubuntu-14_04-amd64

00:00:34

passed #225351
dind allowed to fail
docker_ubuntu-16_04-amd64

00:00:35

 
  Build
passed #225358
amd64 linux docker
build-centos-6-amd64

00:01:10

passed #225359
amd64 linux docker
build-centos-7-amd64

00:01:13

passed #225352
amd64 linux docker
build-debian-7-amd64

00:00:59

passed #225363
amd64 linux docker
build-debian-7-i386

00:01:17

passed #225353
amd64 linux docker
build-debian-8-amd64

00:01:00

passed #225364
amd64 linux docker
build-debian-8-i386

00:01:23

passed #225354
amd64 linux docker
build-debian-9-amd64

00:01:11

passed #225365
amd64 linux docker
build-debian-9-i386

00:01:25

passed #225355
amd64 linux docker
build-debian-testing-amd64

00:01:16

passed #225366
amd64 linux docker
build-debian-testing-i386

00:02:09

passed #225356
amd64 linux docker
build-fedora-25-amd64

00:01:14

passed #225357
amd64 linux docker
build-fedora-26-amd64

00:01:23

passed #225367
amd64 freebsd
build-freebsd-11-amd64

00:02:38

passed #225368
i386 freebsd
build-freebsd-11-i386

00:02:33

passed #225360
amd64 linux docker
build-opensuse-42_3-amd64

00:01:16

passed #225361
amd64 linux docker
build-ubuntu-14_04-amd64

00:01:16

passed #225362
amd64 linux docker
build-ubuntu-16_04-amd64

00:01:18