toaster and kirkstone

Hi,

I heard discussion that toaster wasn't working with kirkstone/master so I looked
into it a bit.

The issue I found was that it was using IMAGE_INSTALL_append instead of
IMAGE_INSTALL:append. I've fixed this on the bitbake list and with that fix
applied, I was able to run a build with it from the UI.

I suspect there is something wrong with the migrations as I had to wipe the
toaster DB and clean out everything to get the change to apply. Help from
toaster literate people would be welcome on that.

I'll probably merge what I've sent and hope someone can work out if there is any
other missing piece.

I did test on a system that probably doesn't have the expat security fixes. I'll
update it and see if things still work.

Cheers,

Richard