Add missing recent versions of vddk to library load list

Add the following versions of vddk to the list to search:
5.5.2
5.5.1
5.1.3
5.1.2
5.1.1
5.0.4
Remove VixDiskLibClient Log Message References

- Since VixDiskLibClient.rb was renamed to VixDiskLib.rb by the last
commit, this will change all references to "VixDiskLibClient" in log
messages printed in this file to "VixDiskLib".
- Remove the spec testing the command line for the smart_proxy_worker
since the change to the lib path is removed by the first commit in
this pull request.

Conflicts:
	lib/VixDiskLib/VixDiskLib.rb
Don't build the c binding to vddk.

https://bugzilla.redhat.com/show_bug.cgi?id=1122264

Related to #277
Remove Support for VixDiskLib 5.1.0

VixDiskLib 5.1.0 has a known bug intermittently causing a
segfault during disk open operations when the vCenter Server
does not provide an SSL thumbprint for the target host.  The
error depends upon the memory content.  This segfault has been
encountered during testing so support for this version has
been removed.  Only this version has this flaw.

Add capability to easily add other unsupported versions along
with a concise reason to be printed to the log.
Return VixDiskLib Load Error to DRB Client

When VixDiskLibServer fails to successfully load any
version of the VixDiskLib, cache the failure reason.
Interrogate for the error once the DRB service is started
so that the failure reason can be passed back to the client
for presentation in the UI. Then shut down the DRB service.
CHerry-pick conflict resolution.