Don't use _units attrs for distances/angles on javascript side
Don't use _units attrs for distances/angles on javascript side

This is problematic without a lot more work, because unlike on the
Python side it isn't kept in sync with the dictionary for the spec
value, leading to weird results such as:

 - if Python side did not send units, setting them on the JS side
   would not send the new units to the Python side
 - if Python side did send units (which I think it always does
   right now), then setting them on the JS side would do
   nothing - this is what always happens right now I believe
 - we don't listen to changes on _units attr, so setting after
   initial creation wouldn't work
 - reading the _units attr would not get the value from the
   spec dict, if the _units attr were unset, so reading _units
   didn't really work

dennisobrien/bokeh,stonebig/bokeh,aiguofer/bokeh,aavanian/bokeh,azjps/bokeh,phobson/bokeh,bokeh/bokeh,timsnyder/bokeh,clairetang6/bokeh,ptitjano/bokeh,phobson/bokeh,htygithub/bokeh,justacec/bokeh,rs2/bokeh,bokeh/bokeh,KasperPRasmussen/bokeh,dennisobrien/bokeh,percyfal/bokeh,htygithub/bokeh,timsnyder/bokeh,bokeh/bokeh,DuCorey/bokeh,percyfal/bokeh,azjps/bokeh,DuCorey/bokeh,philippjfr/bokeh,msarahan/bokeh,stonebig/bokeh,ericmjl/bokeh,maxalbert/bokeh,draperjames/bokeh,maxalbert/bokeh,phobson/bokeh,mindriot101/bokeh,jakirkham/bokeh,aavanian/bokeh,bokeh/bokeh,azjps/bokeh,draperjames/bokeh,bokeh/bokeh,msarahan/bokeh,aiguofer/bokeh,ptitjano/bokeh,quasiben/bokeh,mindriot101/bokeh,aiguofer/bokeh,jakirkham/bokeh,schoolie/bokeh,jakirkham/bokeh,htygithub/bokeh,draperjames/bokeh,timsnyder/bokeh,percyfal/bokeh,draperjames/bokeh,clairetang6/bokeh,aiguofer/bokeh,justacec/bokeh,justacec/bokeh,rs2/bokeh,Karel-van-de-Plassche/bokeh,DuCorey/bokeh,timsnyder/bokeh,draperjames/bokeh,Karel-van-de-Plassche/bokeh,azjps/bokeh,rs2/bokeh,Karel-van-de-Plassche/bokeh,schoolie/bokeh,dennisobrien/bokeh,ericmjl/bokeh,maxalbert/bokeh,philippjfr/bokeh,KasperPRasmussen/bokeh,dennisobrien/bokeh,ericmjl/bokeh,ptitjano/bokeh,ericmjl/bokeh,maxalbert/bokeh,philippjfr/bokeh,htygithub/bokeh,aavanian/bokeh,aiguofer/bokeh,mindriot101/bokeh,KasperPRasmussen/bokeh,percyfal/bokeh,clairetang6/bokeh,rs2/bokeh,KasperPRasmussen/bokeh,mindriot101/bokeh,schoolie/bokeh,rs2/bokeh,stonebig/bokeh,schoolie/bokeh,phobson/bokeh,azjps/bokeh,msarahan/bokeh,ptitjano/bokeh,timsnyder/bokeh,philippjfr/bokeh,aavanian/bokeh,Karel-van-de-Plassche/bokeh,msarahan/bokeh,jakirkham/bokeh,ericmjl/bokeh,dennisobrien/bokeh,phobson/bokeh,percyfal/bokeh,schoolie/bokeh,stonebig/bokeh,ptitjano/bokeh,jakirkham/bokeh,DuCorey/bokeh,aavanian/bokeh,clairetang6/bokeh,DuCorey/bokeh,quasiben/bokeh,Karel-van-de-Plassche/bokeh,justacec/bokeh,KasperPRasmussen/bokeh,philippjfr/bokeh,quasiben/bokeh