Improve PATH handling

I was having issues with .zsh files being loaded before the PATH was
set. I am tired of the band-aid solutions, so now I am going to load all
path.zsh files before I load anything else.
Turn off mouse-resize-pane for tmux

Having mouse-resize-pane as a default is killing me. I want to copy and
paste things with my mouse. That would be nice. This does that.
Handle 't subl' with some grace.

todo.sh does not like it when I ask it to run executables that do not
exist.
Add an 'hr' command

Just a neat little utility. Useful for when you have to mark your place
in history.