Update of the project page / add link in the texdoc

[jonasstein]

Thank you very much for your effort on synctex. It is very helpful for me.

I tried to find the upstream project homepage. I looked in texdoc synctex and man synctex but could not find a link. I suggest to put a link there to this repository.

Finally I found this old confusing website: http://itexmac.sourceforge.net/SyncTeX.html could you update it and put a link to this one?