There was a change in how the iOS webdriver version gets built in selenium

It no longer gets created in the Release-iphonesimulator directory, but instead the Debug-iphonesimulator

because of this, the ios extension will always build webdriver and fail to install it, since it is looking in the wrong place.

https://code.google.com/p/selenium/source/detail?r=18137

This is where it was changed in selenium and the reason they are keeping it

Simple fix PR incoming