chromebook/chromebook-next revised package builds

These PKGBUILDS should be a start based on the discussion I had with leming in #archlinux-arm.  I took the chromebook package and split it up using linux-mvebu as an example.  It builds two sub-packages - one for samsung and one for hp.  It also fixes the outstanding BT_HID bug while I'm here by adding that module.  And for one additional thing, the package specifies a specific git commit to use in order to keep the rolling releases from rolling along.  

linux-chromebook-next is essentially the same thing built on the chromeos-3.8 branch of the kernel-next chromeos repository.  I've been using it for the last few days but it certainly needs more testing (and I have a Spring unlike most folks with the Snow).  The config file is a hybrid of the recommended additions from the ChromiumOS kernel config, blended with the Arch kernel config as well as some personal preferences.  I'm sure that needs some cleanup.  Much changed between the branches but 3.8 supports more hardware on my HP than the 3.4 branch.  

This is actually my first my first pull request and I'm sure I've done plenty of things wrong.  But I wanted to open this for discussion / fixing.  I know the forum says that these need to be tested on archs; I'm using them on the Spring but I'm afraid I don't have a Snow to test on and I'd imagine those are the more populous Daisy's out there.