8082 last(1) should be able to print years in output
For larger wtmpx files it is necessary to get also the year in the output for logins from the last(1) command.

This change implements it in the way that last will now support a -l parameter for long output.
A short explanation why I chose -l:
POSIX itself says nothing about the last command, so this was no reference.
FreeBSD has the -y switch to show years and -w to show also seconds, GNU/Linux has -F to print full login and logout times and dates.

I personally think that it is not necessary to print a full date/time string for login and logout, since the delta (time logged on) is also show (even prefixed with days).

So to shorten the length of the output line, I think it is enough to print the full date7time string on login (and additionally the seconds on logout).

olbohlen@oldn90700:.../illumos-gate/usr/src/cmd/last$ git pbchk                

Man page format/spelling:

mandoc: ../../man/man1/last.1:19:2: WARNING: skipping paragraph macro: sp after SH

mandoc: ../../man/man1/last.1:59:2: WARNING: skipping paragraph macro: sp after SH

mandoc: ../../man/man1/last.1:102:2: WARNING: skipping paragraph macro: sp after SH

mandoc: ../../man/man1/last.1:107:2: WARNING: skipping paragraph macro: sp after SH

mandoc: ../../man/man1/last.1:117:2: WARNING: skipping paragraph macro: sp after SH
olbohlen@oldn90700:.../illumos-gate/usr/src/cmd/last$ /opt/gcc/4.4.4/bin/gcc -o newlast last.c 

olbohlen@oldn90700:.../illumos-gate/usr/src/cmd/last$ ./newlast -h             

usage: last [-n number] [-f filename] [-a ] [ -l ] [name | tty] ...

olbohlen@oldn90700:.../illumos-gate/usr/src/cmd/last$ ./newlast | head         

olbohlen  vt/2         :0               Fri May  5 09:45   still logged in

reboot    system boot                   Fri May  5 09:42 

reboot    system down                   Fri May  5 09:17 

olbohlen  vt/2         :0               Fri May  5 07:22 - 09:16  (01:54)

reboot    system boot                   Fri May  5 07:19 

reboot    system down                   Thu May  4 22:33 

olbohlen  vt/2         :0               Thu May  4 21:22 - 22:31  (01:09)

olbohlen  vt/2         :0               Thu May  4 19:58 - 21:21  (01:23)

olbohlen  vt/2         :0               Thu May  4 19:54 - 19:56  (00:02)

reboot    system boot                   Thu May  4 19:52 

olbohlen@oldn90700:.../illumos-gate/usr/src/cmd/last$ ./newlast -l | head      

olbohlen  vt/2         :0               Fri May  5 09:45:16 2017   still logged in

reboot    system boot                   Fri May  5 09:42:58 2017 

reboot    system down                   Fri May  5 09:17:59 2017 

olbohlen  vt/2         :0               Fri May  5 07:22:37 2017 - 09:16:50  (01:54:13)

reboot    system boot                   Fri May  5 07:19:08 2017 

reboot    system down                   Thu May  4 22:33:05 2017 

olbohlen  vt/2         :0               Thu May  4 21:22:25 2017 - 22:31:55  (01:09:30)

olbohlen  vt/2         :0               Thu May  4 19:58:13 2017 - 21:21:35  (01:23:22)

olbohlen  vt/2         :0               Thu May  4 19:54:37 2017 - 19:56:48  (00:02:11)

reboot    system boot                   Thu May  4 19:52:55 2017 

olbohlen@oldn90700:.../illumos-gate/usr/src/cmd/last$