Uses tempdir module to create/delete xml file

The emc test in cinder is leaving behind its test generated
cinder_emc_config.xml file in /cinder/tests directory.  This
fix uses tempdir module to create the xml file and delete it
when tearDown is called.

Change-Id: I7fd1dda83a097d1122c58cd3ed723ed7f5de30d8
Fixes: bug #1130495
Moved cinder_emc_config.xml.sample to emc folder

Vendor unique driver files should not be placed in /cinder/etc/cinder, but
should stay with the vendors driver.  Moved cinder_emc_config.xml.sample
to cinder/volume/drivers/emc folder.

Change-Id: I92151abdf46a3597ea94284b6dfcf611153cab19
Fixes: bug #1130496
Merge "Moved cinder_emc_config.xml.sample to emc folder"
Merge "Uses tempdir module to create/delete xml file"