Add test for Issue #69
Force focus before testing visibility on focusable elements.

[Finishes #65]
Move GUI only tests into their own test file
Merge pull request #68 from ckundo/dropdown-focus-test

Force focus on elements before checking if they are visible (e.g. skip-nav links)
Fix issues: crash when overlappingElements was null, and text not being computed for hidden elements
Merge pull request #70 from alice/crash

Fix issues: crash when overlappingElements was null, and text not being ...
Check for scrollbars on parent elements
Check scrollWidth; check for overflow = 'hidden' or 'scroll'
Check for clipping by container elements
Merge pull request #71 from alice/scrollArea

Check for focusable element inside scroll area of non-body parents
Check for body element in axs.utils.canScrollTo
Use instanceof check instead of tagName
Merge pull request #72 from alice/scrollArea

Check for body element in axs.utils.canScrollTo()
Create dist/ and related grunt task
Move generated js to dist/js/
Merge pull request #73 from ckundo/create-release-directory

Create release directory and build task
Move license info to the end of the README
Descend into Shadow DOM in AuditRule.collectMatchingElements
Add warning message for rules not supported without console API
Check correct object for warning flag set when no configuration passed.  If configuration supports consoleAPI, do not include rules