Specify arc flags

[tbaranes]

Another key features which could be useful is to add (or not) arc flags if the library doesn't handle but the project does. I think mainly of SKMediaTap, a useful library for OSX which doesn't use arc.

In action, just add the -fno-objc-arc flags to the library concerned.

[devxoul]

Hi @tbaranes! Thank you for idea.

I'm planning to make it available to use additional features via pre/post script. (In order to keep CocoaSeeds simple)
Since pre/post scripting requires flexible architecture, I'm currently working on it.

You can follow #16 for updates.