Added option to ci::Capture to set crossbar for suitable capture device on Windows

Simply extends Capture and CaptureImplDirectShow to allow the creation of Capture with a 'crossbar' option. This is useful for many analog / pci(e) capture devices which have svideo, composite, tuner and so on. 
We definitally can't ignore *.lib's, there are many within cinder's lib folder that need to be updated from time to time. I don't think .gitignore should be modified here at all.