[Click Interaction] Improve poor click interactions for bottom navigation items whose content height is not enough to reach the offset.

[binchoo]

[Test case]
https://jsfiddle.net/1dwxk7nh/4/

[Precondition]

• The height of contents near bottom of the screen is not tall enough to reach the offset of Gumshoe.
• Smooth scrolling disabled.

[Step]

1. Click the nav item: 'Miney'.

[As-Is]

• When 'Miney' is clicked, the screen scrolls to the bottom of document and 'Mo' gets activated.
• In consequence, nav item: 'Miney' never get activated.

[To-Be]

• If a navigation item is clickable and activatable, its click interaction and activation should have consistency.

[binchoo]

Issues on cferdinandi/gumshoe: cferdinandi#127

[binchoo]

Test URL:
https://binchoo.tistory.com/41

Fixed:
36f258d

As-Is:

var spy = new Gumshoe('#my-awesome-nav a', { click: true });

Next: Make it handle smooth scrolling of html/body.