Support more Package Managers in the Dependency Linker

@rspeicher and @DouweM started working on implementing support for a few package managers in gitlab-ce!4121, here's a full list of popular package managers we should consider supporting:

• Bundler/RubyGems (Ruby)
• NPM (Node/JavaScript)
• Composer (PHP)
• Maven (Java)
• Gradle (Java)
• CocoaPods (Obj-C)
• Carthage (Obj-C, alternative to Cocoa Pods which has grown in popularity recently)
• Godep (Go)
• The other Go dependency formats that exist, we have Go devs so just ask them :P
• Pip (Python)
• Hex (Elixir)
• Bower (JS)
• Nuget (.NET)
• Cabal (Haskell)
• Cargo (Rust)
• Rebar (Erlang)

For examples from some of these: https://blog.versioneye.com/2014/01/15/which-programming-language-has-the-best-package-manager/