Major pruning and refactoring. All required logic now resides in the single UIImage+PDF.m. Refactored example project.

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rename : UIImage_PDF_example-Info.plist => Example/Example-Info.plist
rename : UIImage_PDF_example_Prefix.pch => Example/Example_Prefix.pch
rename : README.md => Example/README.md
rename : YingYang.pdf => Example/YingYang.pdf