Add chroot version 2 upgrade script
Add chroot version 2 upgrade script

Add script that adds depot_tools and chromite/bin to the PATH globally using /etc/env.d

BUG=16093
TEST=Ran make_chroot and run_chroot_version_hooks

Change-Id: I6011d7436f18ce46dfe215f01068e862d2567273
Reviewed-on: http://gerrit.chromium.org/gerrit/2022
Reviewed-by: David James <f231dc574bbeb62604660cbc162d1b8642a0a3af@chromium.org>
Tested-by: Ryan Cui <5ce1592d53754a87a44fc2eb7b63d5f77cf50fdb@chromium.org>

smilart/scripts,andrejro/coreos--scripts,mischief/scripts,fivethreeo/scripts,BugRoger/scripts,gtank/scripts,BugRoger/scripts,coreos/scripts,fivethreeo/scripts,crawford/scripts,smilart/scripts,marineam/coreos-scripts,zhang0137/scripts,sigma/coreos-scripts,endocode/scripts,vmware/coreos-scripts,andrejro/coreos--scripts,endocode/scripts,bcwaldon/coreos-scripts,glevand/coreos--scripts,bcwaldon/coreos-scripts,mischief/scripts,andrejro/coreos--scripts,sigma/coreos-scripts,mjg59/scripts,marineam/coreos-scripts,bcwaldon/coreos-scripts,zhang0137/scripts,trnubo/scripts,glevand/coreos--scripts,crawford/scripts,endocode/scripts,nicescale/scripts,marineam/coreos-scripts,crawford/scripts,smilart/scripts,sigma/coreos-scripts,nicescale/scripts,gtank/scripts,trnubo/scripts,mjg59/scripts,mjg59/scripts,trnubo/scripts,vmware/coreos-scripts,mischief/scripts,gtank/scripts,fivethreeo/scripts,zhang0137/scripts,coreos/scripts,vmware/coreos-scripts,BugRoger/scripts,nicescale/scripts