[FEA] Add a function in Hornet that creates a GDF column so that it will be easy to return that value to the user.

[BradReesWork]

Add a function in Hornet that creates a GDF column so that it will be easy to return that value to the user. This will function we be responsible for setting all the internal parameters of the gdf_column so that algorithm developers do not need to worry about understanding cuDF.

• CUDA Code
• Code document
• Test cases

[ogreen]

I already have a partial implementation for this. It will be integrated into Hornet after the big fix is completed.