Remove redundant recommended OSX tool 'autojump' 

autojump 'j' functionality is matched/replaced by fasd 'z' command (installed and enabled as a prezto submodule by default). Instead of typing `j [dirspec]`, you simply type `z [dirspec]`.
Merge pull request #377 from phillipalexander/patch-1

Remove redundant recommended OSX tool 'autojump'  from README.md
tmux: update config

* remove reattach-to-user-namespace
* remove unused key-bindings
* added several key-bindings
* added key-bindings for each window
* replaced user with host on status-left
* polished theme
tmux: set xterm-keys
zsh: clean-up aliases
tmux: control nested sessions
vim: replace neocomplcache with YouCompleteMe
vim: remove most ruby specific plugins