The default transport for the VI API is HTTPS. If the server redirects
from HTTPS to HTTP the driver would silently follow that redirection.
The user assumes to communicate with the server over a secure transport
but isn't.

This patch disables automatical redirection following. The driver reports
an error if the server tries to redirect.

* src/esx/esx_vi.c: refactor the call to curl_easy_perform() into a
  function and do error handling there, disable automatical redirection
  following for curl
* src/esx/esx_vi.h: change the type of responseCode to int

Unified function naming scheme:
- 'lookup' functions query the ESX or vCenter for information
- 'get' functions return information from a local object

* src/esx/esx_driver.c, src/esx/esx_vi.[ch]: unify function naming

An inaccessible datastore has no valid URL property so don't
access its URI property.

* src/esx/esx_vi.c: esxVI_LookupDatastoreByName(): check if datastore is
  accessible before accessing its URL property
* src/esx/esx_vmx.c: update to changed datastore properties

A given domain XML gets converted to a VMX config, uploaded to the host
and registered as new virtual machine.

* src/esx/esx_driver.c: refactor datastore related path parsing into
  esxUtil_ParseDatastoreRelatedPath()
* src/esx/esx_util.[ch]: add esxUtil_ParseDatastoreRelatedPath()
* src/esx/esx_vi.[ch]: add esxVI_Context_UploadFile(), add datastores to
  the traversal in esxVI_BuildFullTraversalSpecList(), add
  esxVI_LookupDatastoreByName()
* src/esx/esx_vi_methods.[ch]: add esxVI_RegisterVM_Task()
* src/esx/esx_vi_types.c: make some error message more verbose
* src/esx/esx_vmx.[ch]: add esxVMX_AbsolutePathToDatastoreRelatedPath()
  to convert a path into a datastore related path, add esxVMX_ParseFileName()
  to convert from VMX path format to domain XML path format, extend the other
  parsing function to be datastore aware, add esxVMX_FormatFileName() to
  convert from domain XML path format to VMX path format, fix VMX ethernet
  entry formating
* tests/esxutilstest.c: add test for esxUtil_ParseDatastoreRelatedPath()
* tests/vmx2xmldata/*: update domain XML files to use datastore related paths
* tests/xml2vmxdata/*: update domain XML files to use datastore related paths,
  update VMX files to use absolute paths

Add esxVI_Occurence enum to describe expected occurence of items
* src/esx/esx_driver.c: update the use of esxVI_LookupVirtualMachineByUuid()
* src/esx/esx_vi.c: add an esxVI_Occurence parameter to
  esxVI_LookupVirtualMachineByUuid() and take care if esxVI_FindByUuid()
  can't find anything for a given uuid
* src/esx/esx_vi.h: add esxVI_Occurence enum
* src/esx/esx_vi_methods.c: expect null or more items to be returned
  from esxVI_FindByUuid()

* src/esx/esx_driver.c: add esxSupportsLongMode() and update esxCapsInit()
* src/esx/esx_vi.[ch]: Add AnyType handling for lists
* src/esx/esx_vi_types.c: bind VI type HostCpuIdInfo

* src/esx/esx_driver.c: add esxNodeGetFreeMemory(), cache IP address
* src/esx/esx_vi.[ch]: refactor resource pool query into esxVI_GetResourcePool()
* src/esx/esx_vi_types.[ch]: bind VI type ResourcePoolResourceUsage

* src/esx/esx_vi.[ch]: convert esxVI_RemoteRequest_Execute() to a
  simpler esxVI_Context_Execute() version, remove esxVI_RemoteRequest
  and convert esxVI_RemoteResponse to esxVI_Response
* src/esx/esx_vi_methods.c: update and simplify callers to use
  esxVI_Context_Execute() instead of esxVI_RemoteRequest_Execute()

* src/esx/esx_vi.[ch]: use virXPathNode*() in
  esxVI_RemoteRequest_Execute() and remove
  esxVI_RemoteResponse_DeserializeXPathObject*()
* src/esx/esx_vi_methods.c: update callers to use the new syntax of
  esxVI_RemoteRequest_Execute()

* src/esx/esx_driver.c: add configStatus to the requested properties
  to check it in esxVI_GetVirtualMachineIdentity()
* src/esx/esx_vi.[ch]: add esxVI_GetManagedEntityStatus()
  and use it in esxVI_GetVirtualMachineIdentity()
* src/esx/esx_vi_types.[ch]: add VI type esxVI_ManagedEntityStatus

* src/esx/esx_driver.c: handle spaces in VMX file path and use a
  virBuffer to encode spaces correctly in the resulting URL
* src/esx/esx_vi.c: include the URL in the error message in case
  of a download error

* src/esx/esx_vi.c (esxVI_Enumeration_Deserialize): Fix
reversed goto and result=-1 statements.

* src/esx/esx_driver.c src/esx/esx_util.[ch] src/esx/esx_vi.[ch]:
  just a name change

* src/esx/esx_driver.c src/esx/esx_vi.[ch] src/esx/esx_vmx.[ch]:
  adds version checking for GSX 2.0, allows to pass a specific port
  for the connection and also add a new specific gsx scheme for
  easier connections to GSX hosts

* src/esx/esx_vi.c: drop host check if no_verify=1, but as Matthias
  pointed out if no_verify=2 we should check the host is the right
  one

* src/esx/esx_driver.c src/esx/esx_vi.c src/esx/esx_vi.h
  src/esx/esx_vmx.c src/esx/esx_vmx.h: extend the VI API version checks
  to accept version 4.0 and takes care of the virtualHW.version change
  from 4 to 7.

* src/esx/esx_driver.c src/esx/esx_util.c src/esx/esx_util.h
  src/esx/esx_vi.c src/esx/esx_vi.h: adds a no_verify query parameter to
  stop libcurl from verifying theserver certificate for the https
  transport.

* src/esx/esx_*.[ch]: the driver, uses a remote minimal SOAP client
  to talk to the VI services on ESX nodes.
* configure.in include/libvirt/virterror.h src/Makefile.am src/driver.h
  src/libvirt.c src/virterror.c: glue in the new driver