Use pfc prefix in config file to set XrdFileCacheOptions.
Update configuration entry.
Make all options lowcase.
Make all options lowcase.
Rename buffersize to blocksize. Rename fileblockmode to filefragmentmode.
Use XrdSysError to print configuration status instead of XrdCl logger.
Rename variable from m_blockSize to m_fileFragmentSize.
Merge pull request #173 from alja/pfc-options

Improvements in XrdFileCache configuration