added conversion from .staves to .vextab
added rendering of .vextab as .pdf using html-pdf
added parsing .staves
added --svg option to enable/disable RaphaelJS
added event-stream to work stream-based now
removed parsing/converting/rendering of staves/vextab/pdf; added modules parser/converter/renderer for that; added stream-based interface (actually not really streamed as es.wait() is called at first)