I don't have an immediate fix to your problem. The problem here is that the evolution-data-server binary package contains some private libraries located in a versioned directory that follow libcamel's versioning. The current structure allow two versions of libcamel to be installed at the same time, but not two versions of evolution-data-server. Maybe the /usr/lib/evolution-data-server-1.2/camel-providers-*/* should belong to the libcamel package?
The good news in a short-term perspective is that as soon as evolution is upgraded to 2.10.1, your evolution will work again. I expect that to happen this week. In the meanwhile, you have to downgrade evolution-data-server in order to have a functional evolution. Still there is a dependency problem, but the solution is not obvious, so we'll have to think through it a couple of times.. Cheers, Øystein