stopping vim from removing indentation on empty lines

Question

When the cursor is placed at the end of a line containing nothing but withspace characters, vim will, when i press enter, remove that whitespace. I find this irritating, as

Answer 1

The Vim wiki suggests this:

inoremap  x

because the indenting is not removed if some text has been entered on the line, even if it has been deleted.

[EDIT - milimetric]

Just a couple of pieces missing from a full solution. You also need remaps for o and O and whatever else you use to add lines:

inoremap  x
nnoremap o ox
nnoremap O Ox

Same idea but people newer to vim might not figure it out quickly.