when sorting csv fixed with files, omit "^"
use "\%v" to get columns pattern (works better with multibyte chars)
syntax highlighting also should use \%v instead of \%c to better match multibyte columns
updated doc
FIX: Avoid GetSID() error when no W mapping.

With :let g:csv_nomap_w = 1, no "W" mapping exists, and the maparg() lookup of the SID fails.
Add a fallback to the alternative algorithm using <sfile>.
Refactoring: Replace s:GetSID() with a cached s:SID value.

As the script's SID is fixed, it needs to be determined only once during sourcing. Remove the version-dependent algorithm that is using maparg(), as this won't work during sourcing. This makes the script simpler and more robust by trading one persisted Integer for runtime function calls.
Merge branch 'master' of https://github.com/chrisbra/csv.vim