core: rhevm-upgrade creates log/helping files...

rhevm-upgrade creates log/helping files in /usr/share/ovirt-engine/dbscripts

1) Adding -g parameter to create_db.sh create_schema.sh and upgrade.sh
to disable MD5 files generation (default NOMD5=false)
2) Adding -m MD5DIR parameter to  create_db.sh create_schema.sh and
upgrade.sh to set the MD% directory (default =MD5DIR=$(pwd))
3) Removing auto-generation of .schema files and creating a
exportDbSchema.sh that generates this file since it is used only for
development

Change-Id: I89b970fdd93102d6354e6cb634af2bd74c0a5dc9
Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=947344
Signed-off-by: Eli Mesika <emesika@redhat.com>