Fix getting of cocoapod version

`pod --version` command, which is used to determine the version of cocoapods, might return some warnings.
Here's a sample output:
```
WARNING: CocoaPods requires your terminal to be using UTF-8 encoding.
Consider adding the following to ~/.profile:

export LANG=en_US.UTF-8

0.39.0
```
Make sure to get the real version in this output (0.39.0).

Author: rosen-vladimirov