Add active/inactive variants of {close,maximize,minimize}-path

[lambdadog]

{close,maximize,minimize}-path->{close,maximize,minimize}-{active,inactive}-path

I chose to go ahead and set up a ButtonState enum and change the config options to enum indexed arrays, since there's discussion in #57 about extending the possible states further.

Note that while I haven't implemented it in this PR in the interest of doing one thing at a time, it may be reasonable to get rid of ButtonState and instead have just a FocusState (or focused boolean value, if you're not concerned about the type system insurance from using a dedicated enum I suppose) on each client and moving every active/inactive switched value to be an array[FocusState, t] where t is their type. Then when adding hover states you could just have the button paths' config types be array[FocusState, array[HoverState, string]].

[codic12]

Looks good to me! Thanks, I'll work on adding support for hovered buttons tomorrow a bit.

[codic12]

Ok, so this might just be an issue with my current setup - certainly a really weird one but I think it is. For some reason, both before and after this PR I think, moving windows around after you set the close-active-path is very laggy, in Xephyr and the native X server.

Do you have this issue? I presume not, and opensuse is just being weird with x11 somehow... I definitely wasn't having this issue on my other arch system.

[lambdadog]

No, I don't have any notable issues, sorry.

[codic12]

Also, in order to not break compatibility, I plan to re-add after all this is implemented close/minimize/maximize-path, which just sets all the states to the same value.