Remove unused and obsolete evolution-data-server-zip.in
Remove libdb related headers from libedata-book.h

This is about e-book-backend-db-cache.h, which is
deprecated. If needed at all, include it directly.
Do not delete passwords during authentication session

The stored password was deleted before actual password prompt
was shown, which is not correct, because the reason to fail with
the stored password can be either that the password on the server
changed or some issue with libsecret, not providing the correct
stored password. As it happens sometimes that the libsecret fails,
then it is quite bad to reenter all the passwords only due to this
reason, thus better do not delete the password at all. The worse
thing on the fact that the password is deleted before the actual
password prompt is shown is that the password prompts pile in a queue,
thus even if the source registry process is killed quickly enough,
at the first false password prompt, all the other stored passwords
are already gone. Not talking that the piled password prompts
can be cancelled meanwhile.
Bug #732948 - Add backend-per-process support

With this we can have all backends running on theirs own processes, in
this way, if a backend crashes we don't have the whole factory crashing
together. Also, each instance of the EBackendFactory can decide if they
want to have all instances of the same backend (like calendar, memo list,
and task list) running in only one process (useful for evolution-ews and
evolution-mapi where we can share the connections between calendar, memo
list and task list) or have each extension running on its own process.
Apart from that, a configure option was added and, in case the user wants
to keep the old behavior, it can be disabled by passing
"--disable-backend-per-process" to the configure.

As a side effect of these changes, we are enforcing that the hash-key
used to keep track of the backend-factories will be built internally and
that *always* will follow the "backend-name:extension-name" structure,
even for ECollectionBackends.