Parquet allow user to specify column encoding

[norberttech]

Currently, PagesBuilder is deciding what type of encoding applies to the columns, and we only support two types:

• RLE_DICTIONARY
• PLAIN

We should allow users to overwrite this, but keep in mind that Booleans should not allow for RLE_DICTIONARY encoding.

I think encoding could be added to NestedColumn/FlatColumn static constructors and used later in PagesBuilder that should fallback to default logic when it's not specified.