Make netctl-auto more hook friendly
The hooks (including any interface hook) are loaded each time a wpa event occurs. This means the auto.action script can be extended in the hooks. For this purpose, several exported variables (mainly $ACTION) can be checked for their value. The name of the active profile is not exported, but still available (just as in ordinary netctl usage) through the $Profile variable. Profiles ending in .action are disallowed (reserved for possible future use). Both ifplugd and wpa_actiond have a notion of 'action script'.