Update to 2.13.1.0.

Start new sentence on new line according to mandoc -T lint

Update to s6 2.13.0.0.

s6-instance-control.8: Remove stray HTML tag. Reported by Carlos Eduardo,
<carana2099@gmail.com>.

Update to 2.12.0.4.

s6-svscanctl.8: fix -i item

s6-svperms(8): add missing dot to Fl macro

Update to s6 2.12.0.2.

Update to s6 2.12.0.0.

Update Makefile.

Add s6-why.7.

LICENSE: Update year range.

Use `MAN_DIR` in Makefile, instead of `MANPATH`.

Update to 2.11.3.0.

Update to 2.11.2.0.

Add ports of multiple pages.

* overview.html
* s6-svscan-1.html
* s6-svscan-not-1.html
* socket-activation.html

Update to 2.11.1.1.

Update to 2.11.1.0.

Merge pull request #7 from kdkasad/fix/install-directories

Makefile: Use `-t` option of install(1).

Fix install(1) usage in Makefile

Without specifying the -t option, install(1) wouldn't create the
destination directories if they didn't already exist. This change fixes
that problem.

Make default Makefile target a no-op.