Fix MacVim by using clang.
Removed useless terminfo wrapping.

Users should manually set the TERMINFO environment variable.
Merge pull request #4576 from cstrahan/macvim-clang

Fix MacVim by using clang.
Merge pull request #4581 from k0ral/tmux

tmux: removed useless terminfo wrapping
pythonPackages.ipython: use correct pythonPackages
pythonPackages: add pyalgotrade
pythonPackages: add scikit-learn