Make interactions darker

Moved opacity up to 0.7 so interaction lines would be darker and more visible.
Add a button for toggline long range interactions

This can turn on or off long range interactions. However this interacts with
the base pair family buttons. So it will only turn them off if the family
button is off as well as turning off the lr button. Not sure this is best
behavior but it is good enough for dev.
Add a data-pdb attribute to the 2D

It's a nicer way of storing what pdb we looking at instead of generating
javascript.
Add basic coloring by RsR

This can now color 2D's by RsR if it exists. This uses the API to get the RsR
values and then can color the 2D. This a very crude version of the needed
functionality.
Merge branch 'dev' of github.com:BGSU-RNA/RNA-3D-Hub into dev