CSS @import hoisting

* CSS import declarations are now hoisted to the top of the <style>
element, thus causing them to work regardless of which stylesheet
passage they're included in.
* Altered window.onerror to print the stack trace if it's available
(currently only in Chrome).
* Fixed the regexes in Passage.prototype.preloadImages, which didn't
detect whitespace correctly.
* Added a check in case an author accidentally uses Passage() instead of
passage() in a story.
Eliminated <br> elements + added Jonah padding

* Jonah: added bottom padding to #passages, so that the present passage
isn't always uncomfortably flush with the bottom of the window.
* Also updated scrollWindowTo() to take a second "margin" argument.
* Wikifier no longer generates <br>s!! Instead, the white-space:
pre-line and white-space: pre-wrap CSS attributes have been added to
.passage and .storyElement. I hope this works as well as it seems to,
because it should simplify various HTML methods in Twine a little bit.
* Altered the MIME-type of ttf and otf to "application/x-font-..."
instead of "application/font-...". Also, unrecognised files are now
"application/octet-stream".
* Added an "identity" setting to StorySettings, which lets you specify a
noun to use for game interface dialog boxes (the restart confirmation,
the error dialog, etc.)
* Removed the unused initialText property from Passage objects, as well
as Passage.prototype.reset.
* To save a little startup time, image passages are no longer
obfuscated.
Expanded the bullet point syntax

* Removed the quote-by-line syntax, on the basis that a good number of
people don't really want indenting that often, and would rather have
greater-than signs as bullet points. The rest can rely on the indented
block syntax (<<<) or HTML.
* Expanded the bullet point syntax. Now, greater-than signs,
equals-signs, hyphens and two-character ASCII right-arrows (->, =>) can
be used to generate special bullet points.
* Removed <<set>>'s defaulting of object properties, due to
inconsistencies when setting multiple variables in one <<set>> tag.
* Nested <ul>s no longer have a margin-top.
Mobile layout CSS for Sugarcane

* I've added a somewhat rudimentary media query to Sugarcane that
converts the sidebar to a vertical header, using a minimum of
alterations, when viewed on a 640px-width display. Hopefully this won't
break custom CSS too much.
* Added <meta> viewport elements to Sugarcane and Jonah (and updated
Responsive's to match) to allow the media query to work on high-DPI
displays.
* Having added the above, Sugarcane's sidebar can now have
position:fixed again.
* Fixed a couple of bugs introduced in previous commits.
Some variegrated fixes

* Game history: Added a test for iOS Safari's private browsing mode,
which does not disable sessionStorage but does reduce its quota to 0 -
making it hard to tell if it's actually usable.
* Removed the - sign from the set of new bullet point symbols, on the
basis that <<print -2>> prints a bullet-pointed "2". Plus, sentences
starting with a - as a hyphen would be affected.
* Removed unused Wikifier code.
* I hope mth doesn't mind being added to the developer list.
Merge pull request #120 from webbedspace/master

Various engine tweaks