Make output column names consistent

[adimascio]

In src/lib/steps.ts, we define the output column name with at least 4 different names:

• newcolumn
• `new_column,
• new_column_name,
• newColumName

Let's pick a single one :).

[adimascio]

Here are my personal choices in decreasing order of preference:

• newcolumn
• new_column
• new_column_name (but please don't choose this one)

The last one simply burns my eyes :)

[davinov]

As this is supposed to live in a js object and then stored as JSON, I recommend following the well-established convention of camelCase.

In Google JSON style guide:

Property names must be camel-cased, ascii strings. https://google.github.io/styleguide/jsoncstyleguide.xml?showone=Property_Name_Format#Property_Name_Format

Therefore, I suggest simply newColumn.

[vdestraitt]

+1 for newColum. We have to think about changing the related doc !