- add all dovecot-*.configfiles as sources

- dont ghost the whole /etc/dovecot. on older rpms the directory is
not created in that case. we only ghost /etc/dovecot/* and have a
%dir entry for /etc/dovecot.

- dont try to delete systemd files when not building with systemd.

- also add dovecot config files for the other 2.x branches

- finally found a way to preserve the configuration even over
version updates.
- have the same ghosting loop in this package as in the
unversioned package
- that way the config files are owned by oth and upgrading to a
newer version of dovecot e.g. 2.3 would also not kill the
config anymore as before.

- added back the old style conflicts to make upgrading easier
- moved copying of the config to the unversioned package

- move the copy part to %postun for handling the upgrading more
graceful.

- we really need the %posttrans for reinstalling the same package

- port changes for the shared unversioned dovecot package from the
2.2 package
- no longer obsolete older packages. module packages require
their base package with version. the main package has a conflicts
on other providers of dovecot-implementation.
- guard the new %pre/%post snippets against missing dovecot
package
- fix https://bugzilla.redhat.com/show_bug.cgi?id=134325: dovecot
should be shut down before exchanging files.
- remove all the init script related scripts from this package.
that we we can break the build cycle more easily.
- copy the example config in post.
- split out all the things we can share with other versioned
dovecot packages.
- no longer obsolete/provide dovecot
- provide dovecot-implementation

- use xz-devel to fix build on SLE 11 SP3