Dial down memory so startup nomount works.

Will fix this later, I think databases that came with the original
Oracle VirtualBox appliances are eating up /dev/shm, which is pretty
small to start with:

    [oracle@localhost ~]$ df -kh
    Filesystem            Size  Used Avail Use% Mounted on
    /dev/hda1              11G  2.4G  7.2G  25% /
    /dev/hdb1              12G  7.2G  3.9G  66% /home
    tmpfs                 444M  370M   75M  84% /dev/shm
    /vagrant              699G  131G  569G  19% /vagrant
Start on create database sql.
Create directories we will use when creating DB.