HPCC-9419 Use environment settings of data2 in file copy

The existing file copy sets secondary data directory based on
predefined replicate directory (which is 'mirror' set by
loadDefaultBases()). This fix sets the secondary data directory using
the environment settings from ESP FileSpray service (the same as the
primary data directory).

To do that, the setting of the secondary data folder has to be read
from ESP request. The existing getClusterPartBaseDir(), getDirectory(),
and getFileDescriptor() are enhanced to read the setting from ESP
request when primary data folder is read. The setting is stored into
class CFileDescriptorBase using enhanced setDefaultDir(). The
queryDefaultDir() in IFileDescriptor is enhanced to access the setting
from IFileDesciptor.

Since file copy function cannot access IFileDescriptor directly, the
setting of the secondary data folder has to be transferred to
IDistributedFile. The setFileAttrs() of class CDistributedFile is
enhanced to transfer the setting into the class. File copy function
uses the setting through enhanced adjustClusterDir() and
queryDefaultDir() at the same position where existing code reads
secondary data folder.

Signed-off-by: Kevin Wang <kevin.wang@lexisnexis.com>