Added ability to customize interval in histogram, issue #7. Also fixed bug that caused editor and panel to be in different scopes

Fix parallel coordinates when used with ordinal/time scales

Adjusts the y-axis and coloring for when ordinal (and as a derivative,
time scales) are the only y-axis in the graph.  Previously, a number-
only axis was required to draw the plot.

Also fixes a bug where selecting ordinal/time scale would not select
the lines.

Closes #54

Fix for micropanel in chrome

Documentation

New Map Panel