Update of libsodium-ios to version 0.4.5

Hi,

this is the update to libsodium-ios 0.4.5

* Updated the base lib to libsodium 0.4.5
* Cocoapods compatible sources included
* Tested with XCode 5.0.2 (iOS7.0.2) and XCode 5.1 DP2 (iOS7.1)

Questions and/or feedback welcome!

Cheers
Mochtu