Expose region name to UI

Enable support for custom region name. This name is use to register the
keystone endpoint. It doesn't support multiple endpoints for different
regions.

related to: https://bugzilla.novell.com/show_bug.cgi?id=896481
Merge pull request #245 from toabctl/add-region-field

Expose region name to UI
Rename region migration

Migration filename should start with 020, not 015. The wrong filename
was introduced in 42676eecca35d93313f2d7c07cc6d0ff94a1c213 .
Merge pull request #246 from toabctl/fix-migration-filename

Rename region migration
Export custom region name in openrc file

OS_REGION_NAME is set to th custom region name set in Crowbar.

related to: https://bugzilla.novell.com/show_bug.cgi?id=896481
Merge pull request #247 from toabctl/region-in-openrc

Export custom region name in openrc file