Fixed: files now save with correct extension in TIFF mode

Also added one little clarification a line or two below.

Fixes #123
Merge remote-tracking branch 'origin/master' into develop
New: highlight now supports a callback function

Also includes support for optional class and id names on highlight boxes.

Fixes from a104b2521e4f0bbab853c5daa043e3952881dd0a also included in source now (put them in build last time).
Fixed: typo in line 95

__image_type -> image_type
Fixed: small changes

Added extra params to highlightOnPages, a css change, a formatting change.
Fixed: highlightOnPage() highlighting current page more than once

highlightOnPage() was highlighting the current page in addition to the page specified in the arguments instead of only that page specified.
Fixed: highlighting happening on current page even if called for another page

_highlight was being called for the current page to display highlights immediately upon calling highlightOnPage(). As such, if your current page was 2, and you called highlightOnPage(3), highlights displayed on both pages 2 and 3. Now, highlights only render immediately if the current page is equal to the one passed to highlightOnPage().

Fixes #128
Formatting: add missing html closing slash
Fixed: update outdated jquery qunit test css url
Fixed: updated jquery qunit test js
Fixed: remove outdated demo.css in favor of diva.min.css
Fixed: unintentionally introduced bug

Had removed 'search-result' from class list for highlights when extra classes were included; this meant the search performed in resetHighlights wouldn't catch the highlight items to remove them.
Fixed: CURLY BRACE

je deteste Allman formatting
Fixed: Outdated parameters of diva test instance updated to reflect current settings
New: added "percentOfWindowWidth" setting to allow the diva-wrapper div to not take the entire page

Will continue to work on this over the weekend/next week, including making the wrapper update correctly and automatically when the page gets resized.
Fixed: outdated function call in fixedHeightGrid() unit test

updated function call.

Addresses #132
Fixed: old function call gotoPage() in public unit test

updated function call.

Addresses #132
Fixed: outdated function calls in toggleFullscreenMode(), enterFullscreen(), leaveFullscreen() unit tests

updated function calls to reflect current codebase.

Addresses #132
Fixed: outdated function calls in Grid View unit tests

Addresses #132
Fixed: outdated function call in public unit tests

updated function call.

Addresses #132