Patching logger to use a ConsoleLogger on a non windows platform.

I was not able to run Octo.exe on OSX because of an issue with the ColoredConsoleAppender in log4net. I was able to move the configuration out to separate embedded files and loading a regular ConsoleAppender when on a non windows environment. I was also able to patch the project file so that it will build in Xamarin Studio.

- Updated Logger to pull log4net configuration from an embedded resource file
- Updated project file to auto restore nuget packages on non-windows platforms
- Created separate logging config files

Original error message:
```
log4net:ERROR Could not create Appender [ConsoleAppender] of type [log4net.Appender.ColoredConsoleAppender]. Reported error follows.
System.EntryPointNotFoundException: GetConsoleOutputCP
  at (wrapper managed-to-native) log4net.Appender.ColoredConsoleAppender:GetConsoleOutputCP ()
  at log4net.Appender.ColoredConsoleAppender.ActivateOptions () [0x00000] in <filename unknown>:0
  at log4net.Repository.Hierarchy.XmlHierarchyConfigurator.ParseAppender (System.Xml.XmlElement appenderElement) [0x00000] in <filename unknown>:0
log4net:ERROR Appender named [ConsoleAppender] not found.
Exit code: -1
```