[vim] Use the diffconflicts plugin
[vim] Use the diffconflicts plugin

The diffconflicts script, which improves the Git mergetool experience,
has now become a Vim plugin.

https://github.com/whiteinge/diffconflicts
https://vim.fandom.com/wiki/A_better_Vimdiff_Git_mergetool

tpenguinltg/dotfiles