Upgrades, added documentation for user in case of errors

We have some known issues which we cannot
address right now, in order to make user's
live better, we decided to add documentation
which will help user to workaround problems
which he can have during the upgrade.

Change-Id: I7381545f027d06d04b4144a466830af1e4a59b92
Closes-bug: #1362685
Merge "Upgrades, added documentation for user in case of errors"