1.1.1 - Minor patch introducing new toggle to hide legends and linked y-axes

Adds some new functionality to the timeline pages. See the changed screenshots in img/ to view what the change looks like. Basically, it's a button that allows the user to hide or show the legends because they sometimes obscure data. I also decided that the y-axes for the occurrence plots (i.e., occurrence and occurrencefi) should be linked together when users zoom.

Other small change involves an internal variable naming inconsistency that Alex pointed out when she did the review for the last patch (end_time and start_time are now consistently endtime and starttime across the code base).