Fix a auctex recipe build bug.

The original auctex recipe build steps will result in a boot error, which tells
that "tex-site.el not found".
Get undo-tree from official git repo
* recipes/gnuplot-mode.rcp: remove extra closed paren
Add Elixir language mode recipe.
Added recipe for f.el
Updated flycheck recipe's dependencies
Update haskell-mode.rcp.

The installation procedure has changed, see
https://github.com/haskell/haskell-mode#installation-from-git .
add recipe for pkg-info & update dependencies for nrepl
Merge pull request #1330 from yyr/master

* recipes/gnuplot-mode.rcp: remove extra closed paren
Merge pull request #1332 from ajstein/emacs-elixir

Add Elixir language mode recipe.
Merge pull request #1337 from toroidal-code/f.el

Added recipe for f.el
Merge pull request #1339 from toroidal-code/flycheck

Updated flycheck recipe's dependencies
Merge pull request #1310 from dholm/undo-tree

Get undo-tree from official git repo
Merge pull request #1298 from 23Skidoo/patch-1

Update haskell-mode.rcp.
Merge pull request #1301 from xiaohanyu/master

Fix a auctex recipe build bug.
add git-modes as dependency for magit
Merge branch 'master' of github.com:dimitri/el-get
New recipe: ido-better-flex.rcp
fix haskell-mode build env and clean hooks