Wrong MariaDB Version for cf-mysql release Bosh

In `db-dumper-service/bin/install-binaries` 
you define 
```
mysql_version="5.7.16"
mysql_global_version="5.7"
mariadb_version="10.2.10"
mongodb_version="3.3.2"
postgresql_version="9.6.1"
```
The cf-mysql bosh Release is on MariaDB 10.1.x and not 10.2. 
