VirStorageVol implementation

VirStorageVol implementation.Adding StorageVolCreateXMLFromFile, StorageVolCreateXML,Delete ,Free and appropriate tests

Adding GetInfo and test

Adding VirStorageVolGetKey, VirStorageVolGetName and appropriate tests

Adding VirStorageVolGetPath and appropriate test

Adding VirStorageVolGetXMLDesc and appropriate test

Adding VirStorageVolLookupByKey,VirStorageVolLookupByName, VirStorageVolLookupByPath and appropriate tests

Adding Resize,Wipe and WipePattern plus appropriate integration tests
Remove some incompatible consts, fix Resize test