Add a dependency on openssl.

Nova and Keystone use openssl to setup certificates.  If it's not
there then Keystone fails with "Error 2: No such file or directory",
Nova fails with "openssl: command not found" and glance fails with
"glance: error: argument --os-auth-token: expected one argument"
Basically, cascading errors everywhere.  So I put the dependency
in "general" since it affects multiple packages.

Fixes bug 1152315

Change-Id: I803f91644443d7aba78c0a90384e32f6eece36ec
Merge "Add a dependency on openssl."