[Merge] lp:~robru/phablet-tools/isolate-upgrades into lp:phablet-tools

[Robert Bruce Park]

This is what citrain script should have been from the start! The problem with 'device-install' was that it could potentially install conflicting silo contents that you weren't supposed to install (because it installed *everything* in the silo) and the problem with 'device-upgrade' was that it would also install things from the archive that weren't in the image, so you weren't really testing against the image state at all, which can also cause problems.

This change causes 'device-upgrade' to isolate the silo, ignoring updates from the distro, installing only the silo contents and then only the silo contents that you already have installed. This therefore solves all the problems with the citrain script making it the ideal way to test silos ;-)
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https://code.launchpad.net/~robru/phablet-tools/isolate-upgrades/+merge/231481
Your team Ubuntu Phablet Team is requested to review the proposed merge of lp:~robru/phablet-tools/isolate-upgrades into lp:phablet-tools.