[SVG] Adds clip operator, fixes setGState, fill, stroke operators

This PR: 
- Adds support for 'clip' operator (Ref: http://www.jagpdf.org/doc/samples/jagpdf_doc_clipping_path.pdf, http://www.jagpdf.org/samples/imageclip.pdf or PDF 32000 spec document (Page 248) ) 
- Fixes setGState to accept args properly (Ref: /test/pdfs/extgstate.pdf)
- Added some missing properties for text & path element (Ref: /test/pdfs/txt2pdf.pdf)
- Fixed viewport transform to include translate (only scaling was done previously) (Ref: /test/pdfs/jai.pdf)
- Added eoFillStroke method (Ref: /test/pdfs/jai.pdf)