fix(vim.eclass): Restore passing --with-tlib=curses to configure

Cross-compiling vim in our environment fails otherwise. The old version
of the eclass had this line but the new one does not. Re-add it to get
things working again. Should investigate this closer before the next
time the eclasses get synced up with Gentoo.
bump(app-editors/vim): sync with upstream

Might as well update since I'm already poking at vim a bit.

Packages updated:
  app-editors/vim
  app-editors/vim-core
Merge pull request #64 from marineam/vim

Vim build fix