Make it obvious to 'dumpxml' readers what unit we are using,
since our default of KiB for memory (1024) differs from qemu's
default of MiB; and differs from our use of bytes for storage.

Tests were updated via:

$ find tests/*data tests/*out -name '*.xml' | \
  xargs sed -i 's/<\(memory\|currentMemory\|hard_limit\|soft_limit\|min_guarantee\|swap_hard_limit\)>/<\1 unit='"'KiB'>/"
$ find tests/*data tests/*out -name '*.xml' | \
  xargs sed -i 's/<\(capacity\|allocation\|available\)>/<\1 unit='"'bytes'>/"

followed by a few fixes for the stragglers.

Note that with this patch, the RNG for <memory> still forbids
validation of anything except unit='KiB', since the code silently
ignores the attribute; a later patch will expand <memory> to allow
scaled input in the code and update the RNG to match.

* docs/schemas/basictypes.rng (unit): Add 'bytes'.
(scaledInteger): New define.
* docs/schemas/storagevol.rng (sizing): Use it.
* docs/schemas/storagepool.rng (sizing): Likewise.
* docs/schemas/domaincommon.rng (memoryKBElement): New define; use
for memory elements.
* src/conf/storage_conf.c (virStoragePoolDefFormat)
(virStorageVolDefFormat): Likewise.
* src/conf/domain_conf.h (_virDomainDef): Document unit used
internally.
* src/conf/storage_conf.h (_virStoragePoolDef, _virStorageVolDef):
Likewise.
* tests/*data/*.xml: Update all tests.
* tests/*out/*.xml: Likewise.
* tests/define-dev-segfault: Likewise.
* tests/openvzutilstest.c (testReadNetworkConf): Likewise.
* tests/qemuargv2xmltest.c (blankProblemElements): Likewise.

* src/conf/domain_conf.h: Add new member "target" to struct
  _virDomainDeviceDriveAddress.

* src/conf/domain_conf.c: Parse and format "target"

* Lots of tests (.xml) in tests/domainsnapshotxml2xmlout,
  tests/qemuxml2argvdata, tests/qemuxml2xmloutdata, and
  tests/vmx2xmldata/ are modified for newly introduced
  attribute "target" for address of "drive" type.

Update test suite accordingly.

Also don't abuse the disk driver name to specify the SCSI controller
model anymore:

  <driver name='buslogic'/>

Use the newly added model attribute of the controller element for this:

  <controller type='scsi' index='0' model='buslogic'/>

The disk driver name approach is deprecated now, but still works for
backward compatibility reasons.

Update the documentation and tests accordingly.

Fix usage of the words controller and id in the VMX handling code. Use
controller, bus and unit properly.

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

* tests/.gitignore: ignore new test binaries
* tests/Makefile.am: add new tests
* tests/esxutilstest.c: test esxVMX_IndexToDiskName()
* tests/vmx2xmldata/*: config files for the VMX to domain XML test
* tests/vmx2xmltest.c: test the VMX to domain XML mapping
* tests/xml2vmxdata/*: config files for the domain XML to VMX test
* tests/xml2vmxtest.c: test the domain XML to VMX mapping