fixed class export method and transposition error

class export still expected parameters from the old function, so
these were removed. The filename path for saving was also trying
to be extracted from the old class attribute self.filename, which
was deprecated and has been replaced by self.exportPath.

There are still some functions that fail when the data matrix is
transposed such that genes are rows instead of columns. the
ANOVA function has now been corrected to allow analysis of transposed
matrices.