CocoaPods/CocoaPods — pull request #426 by farcaller (2012-07-27 09:58:46+00:00)
Title: Fixed a bug with :head download and no prior clone

The bug triggers on missing cache and :head version spec.

### Error

```
No such file or directory - /Users/farcaller/Library/Caches/CocoaPods/Git/ee015ca62af170291abfbddcac2be7db4e7f9d63
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/gems/cocoapods-0.9.2/lib/cocoapods/downloader/git.rb:75:in `chdir'
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/gems/cocoapods-0.9.2/lib/cocoapods/downloader/git.rb:75:in `update_cache'
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/gems/cocoapods-0.9.2/lib/cocoapods/downloader/git.rb:102:in `download_head'
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/gems/cocoapods-0.9.2/lib/cocoapods/downloader/git.rb:143:in `download_head'
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/gems/cocoapods-0.9.2/lib/cocoapods/installer.rb:75:in `download_pod'
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/gems/cocoapods-0.9.2/lib/cocoapods/installer.rb:61:in `block in install_dependencies!'
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/gems/cocoapods-0.9.2/lib/cocoapods/installer.rb:48:in `each'
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/gems/cocoapods-0.9.2/lib/cocoapods/installer.rb:48:in `install_dependencies!'
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/gems/cocoapods-0.9.2/lib/cocoapods/installer.rb:101:in `install!'
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/gems/cocoapods-0.9.2/lib/cocoapods/command/install.rb:53:in `run'
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/gems/cocoapods-0.9.2/lib/cocoapods/command.rb:71:in `run'
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/gems/cocoapods-0.9.2/bin/pod:12:in `'
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/bin/pod:19:in `load'
/Users/farcaller/.rvm/gems/ruby-1.9.3-p125/bin/pod:19:in `

'
```