Merge pull request #7 from wikipathways/dev

Dev
Merge pull request #8 from wikipathways/dev

Dev
Merge pull request #9 from wikipathways/master

latest update
tried using smoothen
elbows appear to be working
elbows OK. curves nowhere close.
elbows working
elbows appear to be working well. curves working so-so
trying to make pathData callback work
callback is messy but working
Merge pull request #10 from wikipathways/master

latest update
Update pan-zoom.css
Update pan-zoom.css
Update pan-zoom.css
Update pan-zoom.css
Update pan-zoom.css
Update pan-zoom.css
Update pan-zoom.css
Update pan-zoom.css
image that shows up during loading is enabled