`wd` not complaining when passed multiple warp points

[lschumm]

The Issue

Suppose we have two warp points set, test1 -> ~/Desktop and test2 -> /dev. If the command

wd test1 test2

is run, then the directory is changed to test2 without any further information. wd should say something like

 * Multiple warp points provided. Please provide only one warp point to wd.

(change to your liking)

Info

zsh 5.2 (x86_64-apple-darwin16.0). MacOS Sierra 10.12.1 (16B2657). MacBookAir7,1. ZSH selected from Terminal -> Preferences -> General -> Shells open with -> Command (complete path): /bin/zsh

[altschuler]

This will be redundant with #17. With this feature wd test1 test2 would warp to <path_to_test1>/test2.