Zip Archive disappear

Hi !

I try to import InMob lib, commited by @ianlevesque

The PodSpec aim at a Zip file.

As usual, CocoaPods should download the zip then unzip it and delete the zip

I can see the zip file being downloaded in the good place, its content is unzipped, but at the end of the install, everything disappeared.

```
ld: warning: directory not found for option '-L/Users/damien/Dev/Projects/auchandrive-ios/Pods/InMobiSDK/InMobi-iOS-SDK-4.0.2/Libs'
ld: library not found for -lInMobi-4.0.2
clang: error: linker command failed with exit code 1 (use -v to see invocation)
```