lib-sieve: Added version to script storage class.

src/lib-sieve/sieve-binary.h

src/lib-sieve/sieve-script.c

src/lib-sieve/sieve-storage-private.h

src/lib-sieve/storage/dict/sieve-dict-storage.c

src/lib-sieve/storage/file/sieve-file-storage.c

src/lib-sieve/storage/ldap/sieve-ldap-storage.c