some atom editor stuff

- suspicious code-cache/ in atom that probably should be ignored
- change in internal config file
Using oh-my-zsh with @holman's dotfiles

- see http://aniketpant.com/2013/04/get-your-dotfiles-straight/
- oh-my-zsh has final word, especially on prompt configuration
- Removing system ls/gls aliases conflicting with zsh
documentation
Setting MY preferences : git, editor and zsh

- adding my gitignore global file
- adding my gitconfig preferences to the template
- using sublime text as default editor
- switched on oh-my-zsh plugins
setting my zsh theme pref