feat: SVD++ should support source DataFrame of other column types #70

It seems GraphFrames SVD++ fails if edges are not exactly of types "long", "long", "double" (scala.MatchError in patten matching on this line)

Perhaps we could support other variations, such as:

• "long", "long", "float"
• "int", "int", "float"
• "int", "int", "double"