VMM/config: Updated Dovecot version check.
Renamed function check_version_format() -> check_dovecot_version().
Now this function checks also if misc.dovecot_version >= MIN_DOVECOT_VERSION.
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Installation
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.. toctree::
:maxdepth: 1
installation/prerequisites
installation/system_preparation
installation/postgresql_configuration
installation/dovecot_configuration
installation/postfix_configuration
installation/install_vmm