Simplify wpa network block creation

It had grown a little diffuse.
Documentation update

Rebuild all the manpages because version information may have changed.

Add a few words on options that are ignored in some cases.
Support more interface types

This allows future connection types to use interfaces other than
networking interfaces, for instance to use USB interfaces.
Merge branch 'master' of github.com:joukewitteveen/netctl into mobile-broadband
Replaced echos with cat.