New windows from current pane path, easy reloading of Tmux

I constantly found myself creating new windows then `cd`'ing into the directory I started the pane from. 

I realized that the vast majority of the time, I was making a new window to be used in the current path, or relatively close to that path. 

So it makes sense to automatically start windows with that path instead of by default having them start in `~/`. If I do need a path relative from home, '~/' is not too hard to type anyway :smile: 

Also, `C-a r` will now instantly reload tmux config. Let me know your thoughts guys!