Introduce OMVFilesystemBackendAbstract::isBlkidEnumerated method. Filesystems identified by the block device identification library are now processed at once to increase performance.

git-svn-id: http://svn.code.sf.net/p/openmediavault/code/trunk@1545 3c3d7b80-5828-415e-9f61-280b98178fff
Add method OMVStorageDeviceHDD::getPowerModeState

git-svn-id: http://svn.code.sf.net/p/openmediavault/code/trunk@1546 3c3d7b80-5828-415e-9f61-280b98178fff
Improve filesystem backend.

git-svn-id: http://svn.code.sf.net/p/openmediavault/code/trunk@1547 3c3d7b80-5828-415e-9f61-280b98178fff