Fix median polish

[smithjessk]

Need to add the log polish and also the probe-level summarization.
Reference: https://github.com/bmbolstad/preprocessCore/blob/409e6100e309001e855dba1b94005c5b3298ec20/src/R_subColSummarize.c#L1585

This is called once for the matrix.
Inside this function, results is a pointer to R_summaries, which is a matrix where col j represents chip j and row i represents the i-th probeset.

[smithjessk]

Reference:
https://github.com/bmbolstad/preprocessCore/blob/409e6100e309001e855dba1b94005c5b3298ec20/src/medianpolish.c#L363

This is called for each probeset separately.
Inside this function, z is a matrix where column j represents chip j and row i represents the i-th probe in this probeset.
resultsSE is the same as buffer above.