css adjustment to fix #40

Sets the tab pane with the same positioning as the parent so it sticks
with it under the conditions already laid out
js adjustment to completely fix #40

This set the measure of the action pane to the height of the nav when
not cropped, but when cropped, it matches the main - (nav head + action
tabs)
Merge pull request #80 from jeremyBass/master

fixes #40