When migrating from other Dovecot based installations it can be very
convenient to just copy over existing hashed passwords.
However, mailcow currently only supports a limited number of password
schemes.
This commit implements all password schemes that do not require
challenge/response or OTP mechanisms.
A convenient way to generate the regex with all supported schemas is
`docker-compose exec dovecot-mailcow doveadm pw -l | awk -F' ' '{printf
"/^{("; for(i=1;i<=NF-1;i++){printf "%s%s", sep, $i; sep="|"}; printf
")}/i\n"}'`
Note that this will also include unsupported challenge/response and OTP
schemas.
Furthermore this increases the vsz_limit for the dovecot auth service to
2G for the use of ARGON2I and ARGON2ID schemas.
Signed-off-by: Felix Kaechele <felix@kaechele.ca>