Password Plugin / LDAP Driver:
- adds support for (optional) multiple userPassword values for compatibility with more authentication shemes
- adds support for CRAM-MD5 scheme as implemented by doveadm pw (credits: see header of plugins/password/helpers/dovecot_hmacmd5.php)
fix indent to match style in ldap.php (tabs to spaces)
Merge pull request #230 from bytesatwork-xx/master

Password Plugin / LDAP Driver: Add support for CRAM-MD5 and multiple userPassword values