Defines an AffymetrixFileSet object by searching for Affymetrix files.
## Static method (use this):
## AffymetrixFileSet$byPath(..., fileClass="AffymetrixFile")## Don't use the below:
# S3 method for AffymetrixFileSet
byPath(static, ..., fileClass="AffymetrixFile")
Returns an AffymetrixFileSet object.
Additional arguments passed to the constructor of the static (calling) class.
The name of the GenericDataFile class.
Note that files with names starting with a period . are not
  searched for.  The reason for this is that such files are reserved for
  internal use of this package.  For instance, the package store average
  signals across CEL files in a file named as .average<something>.CEL
  in the same directory as the CEL files, and when such a directory is
  scanned we do not want such files to be interpreted as data.
For more information see AffymetrixFileSet.