Updated Release: NPOI 2.0 beta 2

a. shiftrow issue in XSSFSheet
b. fix performance issue due to XmlSerializer. NPOI is getting rid of XmlSerializer.
c. reading/writing CT_Drawing
d. ddd pattern issue in CellDateFormatter
e. Change some common interfaces in NPOI.SS
f. fix OutOfMemory issue in MemoryPackagePart
g. Able to read AbsoluteAnchor, OneCellAnchor, TwoCellAnchor in drawing.xml
h. Support Scatter chart in XSSF (xlsx)
g. Extract pictures from Excel (xlsx)