[idempotence] begin overlay refactor.
[idempotence] rewrite show_message()
[idempotence] rewrite prev and next navigation methods
[idempotence] new styles for shadows & bubbles. re-tool bubbles.
[idempotence] cleanup css
[idempotence] cleanup js
[idempotence] fix tests and implement bubble click
[idempotence] fix bubble nav tests, excise that=this, re-compile
[idempotence] add updateVisible method and track current selector
DOCS! DOCS! DOCS DOCS DOCS!
[idempotence] add tests for target element changes
[idempotence] store container elements, remove unnecessary "px"
Merge branch 'master' into idempotence
Merge branch 'benchmark' into idempotence

Conflicts:
	dist/js/pageguide.min.js
	js/pageguide.js
Merge branch 'master' into idempotence

Conflicts:
	dist/js/pageguide.min.js
[idempotence] pointer-events:none for overlays, plus click event passthrough for older browsers
[idempotence] multiple pageguides!!
[idempotence] handle timers better for multiple pageguides
[idempotence] test 2 pageguides 1 page
[idempotence] dedupe forward & back events for multiple pageguides, fix bubble click