Add support for daemon-mode Emacs.

[somesoup]

Modify the check for display-graphic-p to include daemonp so that colors get defined even when no frames are open in a display manager.

[rien333]

@somesoup any idea if this still works?

[jakobwinkler]

For my setup this is still working (and required to get emacsclient to open). I'd be very happy if this could be merged.

[ssnnoo]

Does anyone know if this will go in at some point? Though there are not conflicts...

[EdwardIII]

~~Hey @somesoup looks like there are conflicts now, maybe you could do a rebase to make it more of a no-brainer for @arcticicestudio to review?~~

Edit: Actually having looked a bit deeper this might cause problems, as daemonp doesn't necessarily mean high colour mode. Someone could use the daemon but still start their client in the console. So maybe time to close this off?

Demo of what happens to console if you do use this technique: