substitute AlignedArray with a regular array

[Anipik]

This issue tracks the progress with removing the aligned array.

The aligned array wont make much difference here as we do a lot of move operation.

More Discussion #383

Rough Implementation :- https://github.com/Anipik/machinelearning/tree/temp

This branch removes all the aligned array code from src as well as implementation. All the tests are passing
Will update the issue with performance numbers soon

cc @danmosemsft @tannergooding @TomFinley @eerhardt

[wschin]

What kind of perf do you want to have? How large the data sets are being targeted? For large-scale ML, one representative example is training FFM (a user of AlignedArray) on Criteo. Could you give it a try with your changes? Thanks.

[artidoro]

@Anipik was this issue solved with #1274?

[Anipik]

no its yet to be completed